research article common fixed point results for mappings...
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Hindawi Publishing CorporationAbstract and Applied AnalysisVolume 2013 Article ID 549518 11 pageshttpdxdoiorg1011552013549518
Research ArticleCommon Fixed Point Results for Mappings withRational Expressions
M A Kutbi1 Jamshaid Ahmad2 Nawab Hussain1 and Muhammad Arshad3
1 Department of Mathematics King Abdulaziz University Jeddah Saudi Arabia2Department of Mathematics COMSATS Institute of Information Technology Chak Shahzad Islamabad 44000 Pakistan3 Department of Mathematics International Islamic University Sector H-10 Islamabad 44000 Pakistan
Correspondence should be addressed to Jamshaid Ahmad jamshaid jasimyahoocom
Received 2 March 2013 Accepted 14 May 2013
Academic Editor Irena Rachunkova
Copyright copy 2013 M A Kutbi et al This is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited
We obtain some common fixed point results for single as well as set valued mappings involving certain rational expressions incomplete partial metric spaces In the process we generalize various results of the literature Two examples are also included toillustrate the fact that our results cannot be obtained from the corresponding results in metric spaces
1 Introduction and Preliminaries
In 1994 Matthews [1] introduced the concept of a partialmetric space and obtained a Banach type fixed point theoremon a complete partial metric space Later on several authors(see eg [1ndash28]) proved fixed point theorems in partialmetric spaces After the definition of the Partial Hausdorffmetric Aydi et al [9] proved Banach type fixed point resultfor set valued mappings in complete partial metric spaceHere we prove some common fixed point results for singleas well as set valued mappings involving certain rationalexpressions in complete partial metric spaces and show byexamples that the results proved in this paper cannot bededuced from the corresponding results inmetric spaces (seeExample 10 Remark 13)
We start with recalling some basic definitions and lemmason partial metric space The definition of a partial metricspace is given by Matthews (see [1]) as follows
Definition 1 A partial metric on a nonempty set 119883 is afunction 119901 119883 times 119883 rarr [0infin) such that for all 119909 119910 119911 isin 119883
(P1) 119901(119909 119909) = 119901(119910 119910) = 119901(119909 119910) if and only if 119909 = 119910
(P2) 119901(119909 119909) le 119901(119909 119910)
(P3) 119901(119909 119910) = 119901(119910 119909)
(P4) 119901(119909 119911) le 119901(119909 119910) + 119901(119910 119911) minus 119901(119910 119910)
The pair (119883 119901) is then called a partial metric spaceIf (119883 119901) is a partial metric space then the function 119901
119904
119883times119883 rarr R+ given by 119901119904(119909 119910) = 2119901(119909 119910)minus119901(119909 119909)minus119901(119910 119910)
119909 119910 isin 119883 is a metric on119883A basic example of a partial metric space is the pair
(119877+ 119901) where 119901(119909 119910) = max119909 119910 for all 119909 119910 isin 119877
+
Lemma 2 (see [1]) Let (119883 119901) be a partial metric space thenone has the following
(1) A sequence 119909119899 in a partial metric space (119883 119901)
converges to a point 119909 isin 119883 if and only iflim119899rarrinfin
119901(119909 119909119899) = 119901(119909 119909)
(2) A sequence 119909119899 in a partialmetric space (119883 119901) is called
a Cauchy sequence if the lim119899119898rarrinfin
119901(119909119899 119909119898) exists
and is finite
(3) A partial metric space (119883 119901) is said to be complete ifevery Cauchy sequence 119909
119899 in 119883 converges to a point
119909 isin 119883 that is 119901(119909 119909) = lim119899119898rarrinfin
119901(119909119899 119909119898)
(4) A partial metric space (119883 119901) is complete if and onlyif the metric space (119883 119901
119904) is complete Furthermore
lim119899rarrinfin
119901119904(119909119899 119911) = 0 if and only if 119901(119911 119911) =
lim119899rarrinfin
119901(119909119899 119911) = lim
119899119898rarrinfin119901(119909119899 119909119898)
2 Abstract and Applied Analysis
Remark 3 (see [1]) Let (119883 119901) be a partial metric space andlet 119860 be a nonempty set in (119883 119901) then 119886 isin 119860 if and only if
119901 (119886 119860) = 119901 (119886 119886) (1)
where 119860 denotes the closure of 119860 with respect to the partialmetric 119901 Note 119860 is closed in (119883 119901) if and only if 119860 = 119860
Definition 4 (see [24]) Two families of self-mappings 119879119894119898
1
and 119878119894119899
1are said to be pairwise commuting if
(1) 119879119894119879119895= 119879119895119879119894 119894 119895 isin 1 2 119898
(2) 119878119896119878119897= 119878119897119878119896 119896 119897 isin 1 2 119899
(3) 119879119894119878119896= 119878119896119879119894 119894 isin 1 2 119898 119896 isin 1 2 119899
Now we recall the following definitions and results from[9]
Let 119862119861119901(119883) be the collection of all nonempty closed and
bounded subsets of119883with respect to the partial metric119901 For119860 isin 119862119861
119901(119883) we define
119901 (119886 119860) = inf 119901 (119886 119909) 119909 isin 119860 (2)
For 119860 119861 isin 119862119861119901(119883)
120575119901(119860 119861) = sup 119901 (119886 119861) 119886 isin 119860
120575119901(119861 119860) = sup 119901 (119887 119860) 119887 isin 119861
(3)
For 119860 119861 isin 119862119861119901(119883)
119867119901(119860 119861) = max 120575
119901(119860 119861) 120575
119901(119861 119860) (4)
Proposition 5 (see [9]) Let (119883 119901) be a partial metric spaceFor any 119860 119861 119862 isin 119862119861
119901(119883) one has
(i) 120575119901(119860 119860) = sup119901(119886 119886) 119886 isin 119860
(ii) 120575119901(119860 119860) le 120575
119901(119860 119861)
(iii) 120575119901(119860 119861) = 0 implies that 119860 sube 119861
(iv) 120575119901(119860 119861) le 120575
119901(119860 119862) + 120575
119901(119862 119861) minus inf
119888isin119862119901(119888 119888)
Proposition 6 (see [9]) Let (119883 119901) be a partial metric spaceFor any 119860 119861 119862 isin 119862119861
119901(119883) one has
(h1) 119867119901(119860 119860) le 119867
119901(119860 119861)
(h2) 119867119901(119860 119861) = 119867
119901(119861 119860)
(h3) 119867119901(119860 119861) le 119867
119901(119860 119862) + 119867
119901(119862 119861) minus inf
119888isin119862119901(119888 119888)
Lemma 7 (see [9]) Let 119860 and 119861 be nonempty closed andbounded subsets of a partial metric space (119883 119901) and ℎ gt 1Then for every 119886 isin 119860 there exists 119887 isin 119861 such that 119901(119886 119887) le
ℎ119867119901(119860 119861)
Lemma 8 (see [10]) Let 119860 and 119861 be nonempty closed andbounded subsets of a partialmetric space (119883 119901) and 0 lt ℎ isin RThen for every 119886 isin 119860 there exists 119887 isin 119861 such that 119901(119886 119887) le
119867119901(119860 119861) + ℎ
2 Results for Single Valued Mappings
The following result regarding the existence of the commonfixed point of themappings satisfying a contractive conditionon the closed ball is very useful in the sense that it requiresthe contractiveness of the mappings only on the closed ballinstead of the whole space
Theorem 9 Let 119878 119879 119883 rarr 119883 be mappings on a completePMS (119883 119901) and 119909
0 119909 119910 isin 119883 and 119903 gt 0 Suppose that there
exist nonnegative reals 120572 120573 and 120574 such that 120572 + 120573 + 2120574 lt 1 If119878 and 119879 satisfy
119901 (119878119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119878119909) 119901 (119910 119879119910) + 120574119901 (119910 119878119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(5)
for all 119909 119910 isin 119861119901(1199090 119903)
119901 (1199090 1198781199090) le (1 minus 120582) (119903 + 119901 (119909
0 1199090)) (6)
where 120582 = (120572+ 120574)(1 minus120573minus 120574) Then there exists a unique point119906 isin 119861119901(1199090 119903) such that 119906 = 119878119906 = 119879119906 Also 119901(119906 119906) = 0
Proof Let 1199090be an arbitrary point in119883 and define
1199092119896+1
= 1198781199092119896 1199092119896+2
= 1198791199092119896+1
where 119896 = 0 1 2
(7)
We will prove that 119909119899
isin (119861(1199090 119903)) for all 119899 isin N by
mathematical induction Using inequality (6) and the factthat 120582 = (120572 + 120574)(1 minus 120573 minus 120574) lt 1 we have
119901 (1199090 1198781199090) le 119903 + 119901 (119909
0 1199090) (8)
It implies that 1199091
isin (119861(1199090 119903)) Let 119909
2 119909
119895isin 119861(119909
0 119903) for
some 119895 isin 119873 If 119895 = 2119896 + 1 where 119896 = 0 1 2 (119895 minus 1)2 sousing inequality (5) we obtain
119901 (1199092119896+1
1199092119896+2
)
= 119901 (1198781199092119896 1198791199092119896+1
)
le 120572119901 (1199092119896 1199092119896+1
)
+ (120573119901 (1199092119896 1198781199092119896) 119901 (119909
2119896+1 1198791199092119896+1
)
+120574119901 (1199092119896+1
1198781199092119896) 119901 (119909
2119896 1198791199092119896+1
))
times (1 + 119901 (1199092119896 1199092119896+1
))minus1
le 120572119901 (1199092119896 1199092119896+1
)
+ (120573119901 (1199092119896 1199092119896+1
) 119901 (1199092119896+1
1199092119896+2
)
+120574119901 (1199092119896+1
1199092119896+1
) 119901 (1199092119896 1199092119896+2
))
times (1 + 119901 (1199092119896 1199092119896+1
))minus1
Abstract and Applied Analysis 3
le 120572119901 (1199092119896 1199092119896+1
)
+ (120573119901 (1199092119896 1199092119896+1
) 119901 (1199092119896+1
1199092119896+2
)
+120574119901 (1199092119896 1199092119896+1
) 119901 (1199092119896 1199092119896+2
))
times (1 + 119901 (1199092119896 1199092119896+1
))minus1
le 120572119901 (1199092119896 1199092119896+1
) + 120573119901 (1199092119896+1
1199092119896+2
) + 120574119901 (1199092119896 1199092119896+2
)
(9)
as 1 + 119901(1199092119896 1199092119896+1
) gt 119901(1199092119896 1199092119896+1
) and so
119901 (1199092119896+1
1199092119896+2
) le (120572 + 120574
1 minus 120573 minus 120574)119901 (119909
2119896 1199092119896+1
) (10)
which implies that
119901 (1199092119896+1
1199092119896+2
) le 120582119901 (1199092119896 1199092119896+1
) le sdot sdot sdot le 1205822119896+1
119901 (1199090 1199091)
(11)
If 119895 = 2119896 + 2 where 119896 = 0 1 2 (119895 minus 2)2 one can easilyprove that
119901 (1199092119896+2
1199092119896+3
) le 1205822119896+2
119901 (1199090 1199091) (12)
Thus from inequality (11) and (12) we have
119901 (119909119895 119909119895+1
) le 120582119895119901 (1199090 1199091) for some 119895 isin 119873 (13)
Now
119901 (1199090 119909119895+1
) le 119901 (1199090 1199091) + sdot sdot sdot + 119901 (119909
119895 119909119895+1
)
minus [119901 (1199091 1199091) + sdot sdot sdot + 119901 (119909
119895 119909119895)]
le 119901 (1199090 1199091) + sdot sdot sdot + 120582
119895119901 (1199090 1199091)
= 119901 (1199090 1199091) [1 + sdot sdot sdot + 120582
119895minus1+ 120582119895]
le (1 minus 120582) [119903 + 119901 (1199090 1199090)]
(1 minus 120582119895+1
)
1 minus 120582
le 119903 + 119901 (1199090 1199090)
(14)
gives 119909119895+1
isin 119861(1199090 119903) Hence 119909
119899isin 119861(119909
0 119903) for all 119899 isin N One
can easily prove that
119901 (119909119899 119909119899+1
) le 120582119899119901 (1199090 1199091) (13
lowast)
for all 119899 isin N We now show that 119909119899 is a Cauchy sequence
Without loss of generality assume that 119898 gt 119899 Then using(13lowast) and the triangle inequality for partial metrics (P
4) we
have119901 (119909119899 119909119898) le 119901 (119909
119899 119909119899+1
) + 119901 (119909119899+1
119909119898) minus 119901 (119909
119899+1 119909119899+1
)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119898)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119899+2
) + 119901 (119909119899+2
119909119898)
minus 119901 (119909119899+2
119909119899+2
)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119899+2
) + 119901 (119909119899+2
119909119898)
(15)
Inductively we have
0 le 119901 (119909119899 119909119898)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119899+2
) + sdot sdot sdot + 119901 (119909119898minus1
119909119898)
le 120582119899119901 (1199090 1199091) + 120582119899+1
119901 (1199090 1199091) + sdot sdot sdot + 120582
119898minus1119901 (1199090 1199091)
le (120582119899+ 120582119899+1
+ sdot sdot sdot + 120582119898minus1
) 119901 (1199090 1199091)
le (120582119899
1 minus 120582)119901 (119909
0 1199091)
997888rarr 0 as 119899 997888rarr infin (since 0 lt 120582 lt 1)
(16)
Thus
lim119899rarr+infin
119901 (119909119899 119909119898) = 0 (17)
By the definition of 119901119904 we get for any119898 isin Nlowast
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (18)
Hence the sequence 119909119899 is a Cauchy sequence in
(119861(1199090 119903) 119901119904) By Lemma 2(4) 119909
119899 is a Cauchy sequence in
(119861(1199090 119903) 119901) Therefore there exists a point 119906 isin 119861(119909
0 119903) with
lim119899rarrinfin
119909119899
= 119906 Also lim119899rarrinfin
119901119904(119909119899 119906) = 0 Again from
Lemma 2(4) we have
119901 (119906 119906) = lim119899rarr+infin
119901 (119909119899 119906) = lim
119899rarr+infin119901 (119909119899 119909119898) = 0
(19)
By the triangle inequality (P4) we have
119901 (119906 119878119906) le 119901 (119906 1199092119899+2
) + 119901 (1199092119899+2
119878119906) minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (119906 1199092119899+2
) + 119901 (1198791199092119899+1
119878119906)
le 119901 (119906 1199092119899+2
) + 120572119901 (1199092119899+1
119906)
+ (120573119901 (1199092119899+1
1198791199092119899+1
) 119901 (119906 119878119906)
+120574119901 (119906 1198791199092119899+1
) 119901 (1199092119899+1
119878119906))
times (1 + 119901 (1199092119899+1
119906))minus1
le 119901 (119906 1199092119899+2
) + 120572119901 (1199092119899+1
119906)
+ (120573119901 (1199092119899+1
1199092119899+2
) 119901 (119906 119878119906)
+120574119901 (119906 1199092119899+2
) 119901 (1199092119899+1
119878119906))
times (1 + 119901 (1199092119899+1
119906))minus1
(20)
Letting 119899 rarr +infin and using (19) we obtain
119901 (119906 119878119906) = 0 (21)
By (P1) we concluded that 119906 = 119878119906 It follows similarly that
119906 = 119879119906 To prove the uniqueness of common fixed point let
4 Abstract and Applied Analysis
119906lowastisin 119861(119909
0 119903) be another common fixed point of 119878 and119879 that
is 119906lowast = 119878119906lowast= 119879119906lowast Then
119901 (119906 119906lowast) = 119901 (119878119906 119879119906
lowast)
le 120572119901 (119906 119906lowast)
+120573119901 (119906 119878119906) 119901 (119906
lowast 119879119906lowast)+120574119901 (119906
lowast 119878119906) 119901 (119906 119879119906
lowast)
1+119901 (119906 119906lowast)
= 120572119901 (119906 119906lowast) +
120574119901 (119906lowast 119906) 119901 (119906 119906
lowast)
1 + 119901 (119906 119906lowast)
(22)
so that119901(119906 119906lowast) le 120572119901(119906 119906lowast)+120574119901(119906 119906
lowast) because 1+119901(119906 119906
lowast) gt
119901(119906 119906lowast) Therefore 119901(119906 119906
lowast) le (120572 + 120574)119901(119906 119906
lowast) which is a
contradiction so that 119906 = 119906lowast (as 120572 + 120574 lt 1) Hence 119878 and
119879 have a unique common fixed point in 119861(1199090 119903)
Example 10 Let119883 = [0 +infin) endowed with the usual partialmetric 119901 defined by 119901 119883 times 119883 rarr R+ with 119901(119909 119910) =
max119909 119910 Clearly (119883 119901) is a partial metric space Now wedefine 119878 119879 119883 rarr 119883 as
119878 (119909) =
119909
16if 0 le 119909 le 1
119909 minus1
6if 119909 gt 1
119879 (119909) =
5119909
17if 0 le 119909 le 1
119909 minus1
7if 119909 gt 1
(23)
for all 119909 isin 119883 Taking 120572 = 15 120573 = 16 120574 = 18 1199090= 12
and 119903 = 12 then 119861119901(1199090 119903) = [0 1] Also we have 119901(119909
0 1199090) =
max12 12 = 12 120582 = (120572 + 120574)(1 minus 120573 minus 120574) = 3985 with
(1 minus 120582) (119903 + 119901 (1199090 1199090)) =
46
85
119901 (1199090 1198781199090) = 119901 (
1
21
32) =
1
2lt (1 minus 120582) (119903 + 119901 (119909
0 1199090))
(24)
Also if 119909 119910 isin (1 +infin) then
119901 (119878119909 119879119910) = max 119909 minus1
6 119909 minus
1
7 ge
1
5max 119909 119910
+ (1
6max 119909 119909 minus
1
6max 119910 119910 minus
1
7
+1
8max 119910 119909 minus
1
6max 119909 119910 minus
1
7)
times (1 +max 119909 119910)minus1
= 120572119901 (119909 119910)
+120573119901 (119909 119878119909) 119901 (119910 119879119910) + 120574119901 (119910 119878119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(25)
So the contractive condition does not hold on whole of 119883Now if 119909 119910 isin 119861
119901(1199090 119903) then
119901 (119878119909 119879119910) = max 119909
165119910
17 le
1
5max 119909 119910
+ (1
6max 119909 119909 minus
1
6max 119910 119910 minus
1
7
+1
8max 119910 119909 minus
1
6max 119909 119910 minus
1
7)
times (1 +max 119909 119910)minus1
(26)
Therefore all the conditions of Theorem 9 are satisfied Thus0 is the common fixed point of 119878 and 119879 and 119901(0 0) = 0Moreover note that for any metric 119889 on119883
119889 (1198781 1198791) = 119889 (1
165
17) gt
1
5119889 (1 1)
+ (1
6119889 (1
1
16) 119889 (1
5
17)
+1
8119889 (1
1
16) 119889 (1
5
17))
times (1 + 119889 (1 1))minus1
(27)
Therefore commonfixed points of 119878 and119879 cannot be obtainedfrom a metric fixed point theorem
Corollary 11 Let 119878 119879 119883 rarr 119883 be mappings on a completePMS (119883 119901) Suppose that there exist nonnegative reals 120572 120573and 120574 such that 120572 + 120573 + 2120574 lt 1 If 119878 and 119879 satisfy
119901 (119878119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119878119909) 119901 (119910 119879119910) + 120574119901 (119910 119878119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(28)
for all 119909 119910 isin 119883 Then there exists a unique point 119906 isin 119883 suchthat 119906 = 119878119906 = 119879119906 Also 119901(119906 119906) = 0 Further 119878 and 119879 have nofixed point other than 119906
By choosing 120573 = 120574 = 0 in Corollary 11 we get thefollowing corollary
Corollary 12 Let 119878 119879 119883 rarr 119883 be a mappings on completePMS (119883 119901) If 119878 and 119879 satisfy
119901 (119878119909 119879119910) le 120572119901 (119909 119910) (29)
for all 119909 119910 isin 119883 120572 lt 1 (120572 is a nonnegative real) Then 119878 and 119879
have a common fixed point 119906 isin 119883 and 119901(119906 119906) = 0
Remark 13 If we impose Banach type contractive conditionfor a pair 119878 119879 119883 rarr 119883 of mappings on a metric space(119883 119889) that is 119889(119878119909 119879119910) le 120572119889(119909 119910) for all 119909 119910 isin 119883 andthen it follows that 119878119909 = 119879119909 for all 119909 isin 119883 (ie 119878 and 119879 are
Abstract and Applied Analysis 5
equal) Therefore the above condition fails to find commonfixed points of 119878 and 119879 This can be seen as
119889 (1198781 1198791) = 119889 ((1
16) (
5
17)) gt 120572119889 (1 1) = 0 (30)
However the same condition in partial metric space does notassert that 119878 = 119879 This can be seen as by taking the partialmetric same as in Example 10
119901 (1198781 1198791) = 119901 ((1
16) (
5
17)) =
5
17le 120572119901 (1 1) = 120572 (1)
(31)
for any 120572 ge 13 Hence Corollary 12 cannot be obtained froma metric fixed point theorem
Remark 14 By equating 120572 120573 120574 to 0 in all possible combi-nations one can derive a host of corollaries which includeMatthews theorem for mappings defined on a completepartial metric space
By taking 119878 = 119879 in the Theorem 9 we get the followingcorollary
Corollary 15 Let 119879 119883 rarr 119883 be a mapping on a completePMS (119883 119901) and 119909
0 119909 119910 isin 119883 and 119903 gt 0 Suppose that there
exist nonnegative reals 120572 120573 and 120574 such that 120572 + 120573 + 2120574 lt 1 If119879 satisfies
119901 (119879119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119879119909) 119901 (119910 119879119910) + 120574119901 (119910 119879119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(32)
for all 119909 119910 isin 119861119901(1199090 119903)
119901 (1199090 1198791199090) le (1 minus 120582) (119903 + 119901 (119909
0 1199090)) (33)
where 120582 = (120572+ 120574)(1 minus120573minus 120574) Then there exists a unique point119906 isin 119861
119901(1199090 119903) such that 119906 = 119879119906 Also 119901(119906 119906) = 0 Further 119879
has no fixed point other than 119906
By taking 119878 = 119879 in Corollary 11 we get the followingcorollary
Corollary 16 Let 119879 119883 rarr 119883 be a mapping on a completePMS (119883 119901) Suppose that there exist nonnegative reals 120572 120573and 120574 such that 120572 + 120573 + 2120574 lt 1 If 119879 satisfies
119901 (119879119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119879119909) 119901 (119910 119879119910) + 120574119901 (119910 119879119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(34)
for all 119909 119910 isin 119883 Then there exists a unique point 119906 isin 119883 suchthat 119906 = 119879119906 Also 119901(119906 119906) = 0 Further 119879 has no fixed pointother than 119906
Now we give an example in favour of Corollary 16
Example 17 Let 119883 = [0 4] endowed with the usual partialmetric 119901 defined by 119901(119909 119910) = max119909 119910 Clearly (119883 119901) is acomplete partial metric space Now we define 119865 119883 rarr 119883 asfollows
119865 (119909) =
119909
3if 0 le 119909 lt 2
119909
1 + 119909if 2 le 119909 le 4
(35)
for all 119909 isin 119883 Now let 119910 le 119909 If 119909 isin [0 2) (and so 119910 isin [0 2))Then 119901(119865119909 119865119910) = 1199093 119901(119909 119910) = 119909 119901(119909 119865119909) = 119909 119901(119910 119865119910) =
119910 119901(119910 119865119909) = 1199093 119901(119909 119865119910) = 119909 Taking 120572 = 13 120573 = 115120574 = 215 we can prove that all the conditions of Corollary 16are satisfied Now if 119909 isin [2 4] then 119901(119865119909 119865119910) = 119909(1 + 119909)119901(119909 119910) = 119909 119901(119909 119865119909) = 119909 119901(119910 119865119910) = 119910 119901(119910 119865119909) = 119909(1+119909)119901(119909 119865119910) = 119909 and taking 120572 = 13 120573 = 115 120574 = 215 onecan verify the condition of the above corollary Thus all theconditions of Corollary 16 are satisfied and 119906 = 0 is a fixedpoint of the mapping 119865
As an application of Theorem 9 we prove the followingtheorem for two finite families of mappings
Theorem 18 If 119879119894119898
1and 119878
119894119899
1are two pairwise commuting
finite families of self-mapping defined on a complete partialmetric space (119883 119901) such that the mappings 119878 and 119879 (with119879 = 119879
11198792sdot sdot sdot 119879119898and 119878 = 119878
11198782sdot sdot sdot 119878119899) satisfy the contractive
condition (5) then the component maps of the two families119879119894119898
1and 119878
119894119899
1have a unique common fixed point
Proof FromTheorem 9 we can say that the mappings 119879 and119878 have a unique common fixed point 119911 that is 119879119911 = 119878119911 = 119911Now our requirement is to show that 119911 is a common fixedpoint of all the component mappings of both the families Inviewof pairwise commutativity of the families 119879
119894119898
1and 119878
119894119899
1
(for every 1 le 119896 le 119898) we can write 119879119896119911 = 119879
119896119879119911 = 119879119879
119896119911 and
119879119896119911 = 119879119896119878119911 = 119878119879
119896119911 which show that 119879
119896119911 (for every 119896) is also
a common fixed point of 119879 and 119878 By using the uniqueness ofcommonfixed point we canwrite119879
119896119911 = 119911 (for every 119896) which
shows that 119911 is a common fixed point of the family 119879119894119898
1
Using the same argument one can also show that (for every1 le 119896 le 119899) 119878
119896119911 = 119911Thus componentmaps of the two families
119879119894119898
1and 119878
119894119899
1have a unique common fixed point
By setting 1198791= 1198792= sdot sdot sdot = 119879
119898= 119865 and 119878
1= 1198782= sdot sdot sdot =
119878119899= 119866 in Theorem 18 we get the following corollary
Corollary 19 Let 119865 119866 119883 rarr 119883 be two commuting self-mappings defined on a complete PMS (119883 119901) satisfying thecondition
119901 (119865119898119909 119866119899119910)
le 120572119901 (119909 119910)
+120573119901 (119909 119865
119898119909) 119901 (119910 119866
119899119910) + 120574119901 (119910 119865
119898119909) 119901 (119909 119866
119899119910)
1 + 119901 (119909 119910)
(36)
6 Abstract and Applied Analysis
for all 119909 119910 isin 119883 120572 + 120573 + 2120574 lt 1 (120572 120573 and 120574 are nonnegativereals) Then F and G have a unique common fixed point
By setting 119898 = 119899 and 119865 = 119866 = 119879 in Corollary 19 wededuce the following corollary
Corollary 20 Let 119879 119883 rarr 119883 be a mapping defined on acomplete PMS (119883 119901) satisfying the condition
119901 (119879119899119909 119879119899119910)
le 120572119901 (119909 119910)
+120573119901 (119909 119879
119899119909) 119901 (119910 119879
119899119910) + 120574119901 (119910 119879
119899119909) 119901 (119909 119879
119899119910)
1 + 119901 (119909 119910)
(37)
for all 119909 119910 isin 119883 120572 + 120573 + 2120574 lt 1 (120572 120573 and 120574 are nonnegativereals) Then F has a unique fixed point
By setting 120573 = 120574 = 0 we draw following corollary whichcan be viewed as an extension of Bryantrsquos theorem [15] for amapping on a complete PMS (119883 119901)
Corollary 21 Let 119865 119883 rarr 119883 be a mapping on a completePMS (119883 119901) If 119865 satisfies
119901 (119865119899119909 119865119899119910) le 120572119901 (119909 119910) (38)
for all 119909 119910 isin 119883 120572 lt 1 Then 119865 has a unique fixed point
The following example demonstrates the superiority ofBryantrsquos theorem overMatthews theorem on complete partialmetric space
Example 22 Let119883 = [0 4] Define the partial metric 119901 119883 times
119883 rarr R by
119901 (119909 119910) = max 119909 119910 (39)
Then (119883 119901) is a complete partial metric space Let 119865 119883 rarr
119883 be defined as follows
119865 (119909) =
1199092 if 119909 isin [0 1 [
2 if 119909 isin [1 2 [
0 if 119909 isin [2 4]
(40)
Then for 119909 = 0 and 119910 = 1 we get
119901 (119865 (0) 119865 (1)) = 119901 (0 2) = 2 gt 120572119901 (0 1) = 120572 (1) (41)
because 0 le 120572 lt 1 However 1198652 satisfies the requirement ofBryantrsquos theorem and 119911 = 0 is the unique fixed point of 119865
3 Results for Set Valued Mappings
Theorem23 Let (119883 119901) be a complete partial metric space andlet 119878 119879 119883 rarr 119862119861
119901(119883) be mappings such that
119867119901(119878119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119878119909) 119901 (119910 119879119910) + 120574119901 (119910 119878119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(42)
for all 119909 119910 isin 119883 0 le 120572 120573 120574 with 120572 + 120573 + 2120574 lt 1 Then 119878 and 119879
have a common fixed point
Proof Assume that119872 = ((120572 + 120574)(1 minus 120573 minus 120574)) Let 1199090isin 119883 be
arbitrary but fixed element of 119883 and choose 1199091
isin 119878(1199090) By
Lemma 8 we can choose 1199092isin 119879(119909
1) such that
119901 (1199091 1199092) le 119867
119901(119878 (1199090) 119879 (119909
1)) + (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1198781199090) 119901 (119909
1 1198791199091)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199091 1198781199090) 119901 (119909
0 1198791199091)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1199091) 119901 (119909
1 1199092)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199091 1199091) 119901 (119909
0 1199092)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1199091) 119901 (119909
1 1199092)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199090 1199091) 119901 (119909
0 1199092)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573119901 (119909
1 1199092) + 120574119901 (119909
0 1199092)
+ (120572 + 120574)
(43)
So we get
119901 (1199091 1199092) le (
120572 + 120574
1 minus 120573 minus 120574)119901 (119909
0 1199091) + (
120572 + 120574
1 minus 120573 minus 120574) (44)
Since119872 = ((120572 + 120574)(1 minus 120573 minus 120574)) so it further implies that119901 (1199091 1199092) le 119872119901 (119909
0 1199091) + 119872 (45)
By Lemma 8 we can choose 1199093isin 119878(1199092) such that
119901 (1199092 1199093) le 119867
119901(119879 (1199091) 119878 (119909
2)) +
(120572 + 120574)2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1198791199091) 119901 (119909
2 1198781199092)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199092 1198791199091) 119901 (119909
1 1198781199092)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199092 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199091 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
Abstract and Applied Analysis 7
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199091 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573119901 (119909
2 1199093) + 120574119901 (119909
1 1199093)
+(120572 + 120574)
2
1 minus 120573 minus 120574
(46)
So we get
119901 (1199092 1199093) le (
120572 + 120574
1 minus 120573 minus 120574)
2
119901 (1199090 1199091) + 2(
120572 + 120574
1 minus 120573 minus 120574)
2
(47)
Continuing in this manner one can obtain a sequence 119909119899 in
119883 as 1199092119899+1
isin 119878(1199092119899) and 119909
2119899+2isin 119879(119909
2119899+1) such that
119901 (119909119899 119909119899+1
) le 119872119901 (119909119899minus1
119909119899) + 119872
le sdot sdot sdot le 119872119899119901 (1199090 1199091) + 119899119872
119899
(48)
where 119872 = ((120572 + 120573)(1 minus 120572)) lt 1 for all 119899 ge 0 Without lossof generality assume that 119899 gt 119898 Then using (48) and thetriangle inequality for partial metrics (P
4) we have
119901 (119909119899 119909119898)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119899+2
) + sdot sdot sdot + 119901 (119909119898minus1
119909119898)
le 119872119899119901 (1199090 1199091) + 119899119872
119899+ 119872119899+1
119901 (1199090 1199091)
+ (119899 + 1)119872119899+1
+ sdot sdot sdot + 119872119898minus1
119901 (1199090 1199091)
+ (119898 minus 1)119872119898minus1
le
119898minus1
sum
119894=119899
119872119894119901 (1199090 1199091)
+
119898minus1
sum
119894=119899
119894119872119894997888rarr 0 as 119899 997888rarr +infin (since 0 lt 119872 lt 1)
(49)
By the definition of 119901119904 we get
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (50)
This yields that 119909119899 is a Cauchy sequence in (119883 119901
119904) Since
(119883 119901) is complete then from Lemma 2(4) (119883 119901119904) is a com-
plete metric space Therefore the sequence 119909119899 converges
to some 119909lowast
isin 119883 with respect to the metric 119901119904 that is
lim119899rarr+infin
119901119904(119909119899 119909lowast) = 0 Again from Lemma 2(4) we get
119901 (119909lowast 119909lowast) = lim119899rarr+infin
119901 (119909119899 119909lowast) = lim119899rarr+infin
119901 (119909119899 119909119899) = 0 (51)
119867119901(119879 (1199092119899+2
) 119878 (119909lowast))
le 120572119901 (1199092119899+2
119909lowast)
+ 120573119901 (1199092119899+2
119879 (1199092119899+2
)) 119901 (119909lowast 119878 (119909lowast))
1 + 119901 (1199092119899+2
119909lowast)
+ 120574119901 (1199092119899+2
119878 (119909lowast)) 119901 (119909
lowast 119879 (1199092119899+2
))
1 + 119901 (1199092119899+2
119909lowast)
le 120572119901 (1199092119899+2
119909lowast)
+ 120573119901 (1199092119899+2
1199092119899+3
) 119901 (119909lowast 119878 (119909lowast))
1 + 119901 (1199092119899+2
119909lowast)
+ 120574119901 (1199092119899+2
119878 (119909lowast)) 119901 (119909
lowast 1199092119899+1
)
1 + 119901 (1199092119899+2
119909lowast)
(52)
taking limit as 119899 rarr infin and using (51) we get
lim119899rarr+infin
119867119901(119879 (1199092119899+2
) 119878 (119909lowast)) = 0 (53)
Now 1199092119899+1
isin 119879(1199092119899+2
) gives that
119901 (1199092119899+1
119878 (119909lowast)) le 119867
119901(119879 (1199092119899+2
) 119878 (119909lowast)) (54)
which implies that
lim119899rarr+infin
119901 (1199092119899+1
119878 (119909lowast)) = 0 (55)
On the other hand by (P4) we have
119901 (119909lowast 119878 (119909lowast)) le 119901 (119909
lowast 1199092119899+2
) + 119901 (1199092119899+2
119878 (119909lowast))
minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (119909lowast 1199092119899+2
) + 119901 (1199092119899+2
119878 (119909lowast))
(56)
Taking limit as 119899 rarr +infin and using (51) and (55) we obtain119901(119909lowast 119878(119909lowast)) = 0 Therefore from (51) (119901(119909lowast 119909lowast) = 0) we
obtain
119901 (119909lowast 119878 (119909lowast)) = 119901 (119909
lowast 119909lowast) (57)
which from Remark 14 implies that 119909lowast
isin 119878(119909lowast) = 119878(119909lowast)
Similarly one can easily prove that 119909lowast isin 119879(119909lowast) Thus 119878 and
119879 have a common fixed point
Remark 24 For 120573 = 120574 = 0 and 119878 = 119879 Theorem 23 reduces tothe following result of Aydi et al [9]
Corollary 25 (see [9 Theorem 32]) Let (119883 119901) be a partialmetric space If 119879 119883 rarr 119862119861
119901(119883) is a multivalued mapping
such that for all 119909 119910 isin 119883 one has
119867119901(119879119909 119879119910) le 119896119901 (119886 119887) (58)
where 119896 isin (0 1) Then 119879 has a fixed point
8 Abstract and Applied Analysis
Theorem26 Let (119883 119901) be a complete partialmetric space and119878 119879 119883 rarr 119862119861
119901(119883) be multivalued mappings such that
119867119901(119878119909 119879119910) le 120572
119901 (119909 119878119909) 119901 (119909 119879119910) + 119901 (119910 119879119910) 119901 (119910 119878119909)
119901 (119909 119879119910) + 119901 (119910 119878119909)
+ 120573119889 (119909 119910)
(59)
for all 119909 119910 isin 119883 0 le 120572 120573 with 2120572 + 120573 lt 1 and 119901(119909 119879119910) +
119901(119910 119878119909) = 0 Then 119878 and 119879 have a common fixed point
Proof Assume that 119897 = (120572+120573)(1minus120572) Let 1199090isin 119883 be arbitrary
but fixed element of119883 and choose 1199091isin 119878(1199090)
When 119901(119909 119879119910)+119901(119910 119878119909) = 0 By Lemma 8we can choose1199092isin 119879(119909
1) such that
119901 (1199091 1199092)
le 119867119901(119878 (1199090) 119879 (119909
1)) + (120572 + 120573)
le 120572119901 (1199090 1198781199090) 119901 (119909
0 1198791199091) + 119901 (119909
1 1198791199091) 119901 (119909
1 1198781199090)
119901 (1199090 1198791199091) + 119901 (119909
1 1198781199090)
+ 120573119901 (1199090 1199091) + (120572 + 120573)
le 120572119901 (1199090 1199091) 119901 (119909
0 1199092) + 119901 (119909
1 1199092) 119901 (119909
1 1199091)
119901 (1199090 1199092) + 119901 (119909
1 1199091)
+ 120573119901 (1199090 1199091) + (120572 + 120573)
le 120572 119901 (1199090 1199091) + 119901 (119909
1 1199092) + 120573119901 (119909
0 1199091) + (120572 + 120573)
(60)
because 119901(1199090 1199092) lt 119901(119909
0 1199092) + 119901(119909
1 1199091) and 119901(119909
1 1199091) lt
119901(1199091 1199091) + 119901(119909
0 1199092) Thus we get
119901 (1199091 1199092) le (
120572 + 120573
1 minus 120572)119901 (119909
0 1199091) + (
120572 + 120573
1 minus 120572) (61)
It further implies that
119901 (1199091 1199092) le 119897119901 (119909
0 1199091) + 119897 (62)
By Lemma 8 we can choose 1199093isin 119878(1199092) such that
119901 (1199092 1199093)
le 119867119901(119879 (1199091) 119878 (119909
2)) +
(120572 + 120573)2
1 minus 120572
le 120572119901 (1199091 1198791199091) 119901 (119909
1 1198781199092) + 119901 (119909
2 1198781199092) 119901 (119909
2 1198791199091)
119901 (1199091 1198781199092) + 119901 (119909
2 1198791199091)
+ 120573119901 (1199091 1199092) +
(120572 + 120573)2
1 minus 120572
le 120572119901 (1199091 1199092) 119901 (119909
1 1199093) + 119901 (119909
2 1199093) 119901 (119909
2 1199092)
119901 (1199091 1199093) + 119901 (119909
2 1199092)
+ 120573119901 (1199091 1199092) +
(120572 + 120573)2
1 minus 120572
le 120572 119901 (1199091 1199092) + 119901 (119909
2 1199093) + 120573119901 (119909
1 1199092) +
(120572 + 120573)2
1 minus 120572
(63)
because 119901(1199091 1199093) lt 119901(119909
1 1199093) + 119901(119909
2 1199092) and 119901(119909
2 1199092) lt
119901(1199092 1199092) + 119901(119909
1 1199093) Thus we get
119901 (1199092 1199093) le (
120572 + 120573
1 minus 120572)119901 (119909
1 1199092) + (
120572 + 120573
1 minus 120572)
2
(64)
It further implies that
119901 (1199092 1199093) le 1198972119901 (1199090 1199090) + 21198972 (65)
Continuing in this manner one can obtain a sequence 119909119899 in
119883 as 1199092119899+1
isin 119878(1199092119899) and 119909
2119899+2isin 119879(119909
2119899+1) such that
119901 (119909119899 119909119899+1
) le 119897119901 (119909119899minus1
119909119899) + 119897 le sdot sdot sdot le 119897
119899119901 (1199090 1199091) + 119899119897119899
(66)
where 119897 = ((120572 + 120573)(1 minus 120572)) lt 1 for all 119899 ge 0 Withoutloss of generality assume that 119898 gt 119899 Then using (66) andthe triangle inequality for partial metrics (P
4) one can easily
prove that
119901 (119909119899 119909119898) le
119898minus1
sum
119894=119899
119897119894119901 (1199090 1199091) +
119898minus1
sum
119894=119899
119894119897119894
997888rarr 0 as 119899 997888rarr +infin (since 0 lt 119897 lt 1)
(67)
By the definition of 119901119904
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (68)
This yields that 119909119899 is a Cauchy sequence in (119883 119901
119904) Since
(119883 119901) is complete then from Lemma 2(4) (119883 119901119904) is a com-
plete metric space Therefore the sequence 119909119899 converges
to some 1199091015840
isin 119883 with respect to the metric 119901119904 that is
lim119899rarr+infin
119901119904(119909119899 1199091015840) = 0 Again from Lemma 2(4) we get
119901 (1199091015840 1199091015840) = lim119899rarr+infin
119901 (119909119899 119909) = lim119899rarr+infin
119901 (119909119899 119909119899) = 0
(69)
Abstract and Applied Analysis 9
119867119901(119879 (1199092119899+1
) 119878 (1199091015840))
le 120572 (119901 (1199092119899+1
119879 (1199092119899+1
)) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 119879 (1199092119899+1
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 119879 (1199092119899+1
)))minus1
+ 120573119901 (1199092119899+1
119909)
le 120572 (119901 ((1199092119899+1
1199092119899+2
) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 1199092119899+2
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 1199092119899+2
))minus1
+ 120573119901 (1199092119899+1
119909)
(70)
therefore
lim119899rarr+infin
119867119901(119879 (1199092119899+1
) 119878 (1199091015840)) = 0 (71)
Now 1199092119899+2
isin 119879(1199092119899+1
) gives that
119901 (1199092119899+2
119878 (1199091015840)) le 119867
119901(119879 (1199092119899+1
) 119878 (1199091015840)) (72)
which implies that
lim119899rarr+infin
119901 (1199092119899+2
119878 (1199091015840)) = 0 (73)
On the other hand we have
119901 (1199091015840 119878 (1199091015840)) le 119901 (119909
1015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (1199091015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
(74)
Taking limit as 119899 rarr +infin and using (69) and (73) we obtain119901(1199091015840 119878(1199091015840)) = 0 Therefore from (69) (119901(1199091015840 1199091015840) = 0) we
obtain
119901 (1199091015840 119878 (1199091015840)) = 119901 (119909
1015840 1199091015840) (75)
which from Remark 14 implies that 1199091015840
isin 119878(1199091015840) = 119878(1199091015840)
It follows similarly that 1199091015840
isin 119879(1199091015840) Thus 119878 and 119879 have a
common fixed point
Now we give an example which illustrates our Theo-rem 26
Example 27 Let 119883 = 1 2 3 be endowed with usual orderand let 119901 be a partial metric on119883 defined as
119901 (1 1) = 119901 (2 2) = 0 119901 (3 3) =5
11
119901 (1 2) = 119901 (2 1) =3
10
119901 (1 3) = 119901 (3 1) =9
20
119901 (2 3) = 119901 (3 2) =1
2
(76)
Define the mappings 119878 119879 119883 rarr 119862119861119901(119883) by
119878119909 = 1 if 119909 119910 isin 1 2
1 2 otherwise
119879119909 = 1 if 119909 119910 isin 1 2
2 otherwise
(77)
Note that 119878119909 and 119879119909 are closed and bounded for all 119909 isin 119883
with respect to the partial metric 119901 To show that for all 119909 119910in119883 (59) is satisfied with 120572 = 111 120573 = 45 we consider thefollowing cases if 119909 119910 isin 1 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 1) = 0 (78)
and condition (59) is satisfied obviously
If 119909 = 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 2) =
3
10
119901 (119909 119878119909) = 119901 (119910 119878119909) = 119901 (3 1 2) =9
20
119901 (119909 119879119910) = 119901 (119910 119879119910) = 119901 (119910 119878119909) = 119901 (3 2) =11
24
119901 (119909 119910) = 119901 (3 3) =5
11
(79)
If 119909 = 3 119910 = 1 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (1 1) = 0 119901 (119910 119878119909) = 119901 (1 1 2) = 0
119901 (119909 119910) = 119901 (3 1) =9
20
(80)
10 Abstract and Applied Analysis
If 119909 = 3 119910 = 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (2 1) =3
10 119901 (119910 119878119909) = 119901 (2 1 2) = 0
119901 (119909 119910) = 119901 (3 2) =1
2
(81)
If 119909 = 1 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (1 1) = 0 119901 (119909 119879119910) = 119901 (1 2) =3
10
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (1 3) =9
20
(82)
If 119909 = 2 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (2 1) =3
10 119901 (119909 119879119910) = 119901 (2 2) = 0
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (2 3) =1
2
(83)
Thus all the conditions ofTheorem 26 are satisfied Here 119909 =
1 is a common fixed point of 119878 and 119879On the other hand the metric 119901
119904 induced by the partialmetric 119901 is given by
119901119904(1 1) = 119901
119904(2 2) = 119901
119904(3 3) = 0
119901119904(2 1) = 119901
119904(2 1) =
3
4
119901119904(3 2) = 119901
119904(2 3) =
4
7
119901119904(3 1) = 119901
119904(1 3) =
14
29
(84)
Note that in case of ordinary Hausdorff metric given map-ping does not satisfy the condition Indeed for 119909 = 1 and119910 = 3 we have
119867(119878119909 119879119910) = 119867 (1 2) =3
4
119901119904(119909 119878119909) = 119901
119904(1 1) = 0
119901119904(119909 119879119910) = 119901
119904(1 2) =
3
4
119901119904(119910 119879119910) = 119901
119904(3 2) =
4
7
119901119904(119910 119878119909) = 119901
119904(3 1) =
14
29
(85)
for the values of 120572 = 111 120573 = 45 By a routine calculationone can easily verify that the mapping does not satisfy thecondition which involved ordinary Hausdorff metric
Acknowledgment
This paper was funded by the Deanship of Scientific Research(DSR) King Abdulaziz University Jeddah The authorstherefore acknowledge with thanks DSR technical and finan-cial support
References
[1] S G Matthews ldquoPartial metric topologyrdquo in Proceedings of the8th Summer Conference on General Topology and Applicationsvol 728 pp 183ndash197 New York Academy of Science 1994
[2] T Abdeljawad E Karapinar andK Tas ldquoA generalized contrac-tion principle with control functions on partial metric spacesrdquoComputers amp Mathematics with Applications vol 63 no 3 pp716ndash719 2012
[3] T Abdeljawad ldquoFixed points for generalized weakly contractivemappings in partialmetric spacesrdquoMathematical andComputerModelling vol 54 no 11-12 pp 2923ndash2927 2011
[4] J Ahmad M Arshad and C Vetro ldquoOn a theorem of Khan in ageneralized metric spacerdquo International Journal of Analysis vol2013 Article ID 852727 6 pages 2013
[5] S Alsulami N Hussain and A Alotaibi ldquoCoupled fixed andcoincidence points for monotone operators in partial metricspacesrdquo Fixed Point Theory and Applications vol 2012 article173 2012
[6] I Altun and A Erduran ldquoFixed point theorems for monotonemappings on partial metric spacesrdquo Fixed Point Theory andApplications vol 2011 Article ID 508730 2011
[7] M Arshad J Ahmad and E Karapinar ldquoSome common fixedpoint results in rectangularmetric spacesrdquo International Journalof Analysis vol 2013 Article ID 307234 7 pages 2013
[8] M Arshad E Karapinar and J Ahmad ldquoSome unique fixedpoint theorem for rational contractions in partially orderedmetric spacesrdquo Journal of Inequalities andApplications vol 2013article 248 2013
[9] H Aydi M Abbas and C Vetro ldquoPartial Hausdorff metric andNadlerrsquos fixed point theorem on partial metric spacesrdquo Topologyand Its Applications vol 159 no 14 pp 3234ndash3242 2012
Abstract and Applied Analysis 11
[10] H Aydi M Abbas and C Vetro ldquoCommon Fixed points formultivalued generalized contractions on partial metric spacesrdquoRevista de la Real Academia de Ciencias Exactas Fisicas yNaturales A 2013
[11] A Azam and M Arshad ldquoFixed points of a sequence of locallycontractive multivalued mapsrdquo Computers amp Mathematics withApplications vol 57 no 1 pp 96ndash100 2009
[12] A Azam B Fisher and M Khan ldquoCommon fixed point the-orems in complex valued metric spacesrdquo Numerical FunctionalAnalysis and Optimization vol 32 no 3 pp 243ndash253 2011
[13] S Banach ldquoSur les operations dans les ensembles abstraitset leurs applications aux equations integralesrdquo FundamentaMathematicae vol 3 pp 133ndash181 1922
[14] I Beg and A Azam ldquoFixed points of asymptotically regularmultivalued mappingsrdquo Journal of the Australian MathematicalSociety A vol 53 no 3 pp 313ndash326 1992
[15] V W Bryant ldquoA remark on a fixed-point theorem for iteratedmappingsrdquo The American Mathematical Monthly vol 75 pp399ndash400 1968
[16] K P Chi E Karapınar and T D Thanh ldquoA generalizedcontraction principle in partial metric spacesrdquo Mathematicaland Computer Modelling vol 55 no 5-6 pp 1673ndash1681 2012
[17] N Hussain H K Nashine Z Kadelburg and S M AlsulamildquoWeakly isotone increasingmappings and endpoints in partiallyordered metric spacesrdquo Journal of Inequalities and Applicationsvol 2012 article 232 2012
[18] NHussain DDJoric Z Kadelburg and S Radenovic ldquoSuzuki-type fixed point results in metric type spacesrdquo Fixed PointTheory and Applications vol 2012 article 126 2012
[19] N Hussain Z Kadelburg S Radenovic and F R Al-SolamyldquoComparison functions and fixed point results in partial metricspacesrdquo Abstract and Applied Analysis vol 2012 Article ID605781 15 pages 2012
[20] N Hussain and M Abbas ldquoCommon fixed point results fortwo new classes of hybrid pairs in symmetric spacesrdquo AppliedMathematics and Computation vol 218 no 2 pp 542ndash547 2011
[21] S Hong ldquoFixed points of multivalued operators in orderedmetric spaces with applicationsrdquo Nonlinear Analysis TheoryMethods amp Applications vol 72 no 11 pp 3929ndash3942 2010
[22] S Hong ldquoFixed points for mixed monotone multivalued oper-ators in Banach spaces with applicationsrdquo Journal of Mathemat-ical Analysis and Applications vol 337 no 1 pp 333ndash342 2008
[23] S Hong ldquoFixed points of discontinuous multivalued increasingoperators in Banach spaces with applicationsrdquo Journal of Math-ematical Analysis and Applications vol 282 no 1 pp 151ndash1622003
[24] M Imdad J Ali and M Tanveer ldquoCoincidence and commonfixed point theorems for nonlinear contractions in Menger PMspacesrdquo Chaos Solitons amp Fractals vol 42 no 5 pp 3121ndash31292009
[25] E Karapinar ldquoCiric type nonunique fixed point theorems onpartial metric spacesrdquo The Journal of Nonlinear Science andApplications vol 5 no 2 pp 74ndash83 2012
[26] E Karapnar and I M Erhan ldquoFixed point theorems for opera-tors on partial metric spacesrdquo Applied Mathematics Letters vol24 no 11 pp 1894ndash1899 2011
[27] E KarapinarMMarudai andV Pragadeeshwarar ldquoFixed pointtheorems for generalized weak contractions satisfying rationalexpressions on ordered Partial Metric Spacerdquo LobachevskiiJournal of Mathematics vol 34 no 1 pp 116ndash123 2013
[28] M S Khan M Swaleh and M Imdad Some Fixed PointTheorems IV Communications 1983
Submit your manuscripts athttpwwwhindawicom
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Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
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Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Decision SciencesAdvances in
Discrete MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom
Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
2 Abstract and Applied Analysis
Remark 3 (see [1]) Let (119883 119901) be a partial metric space andlet 119860 be a nonempty set in (119883 119901) then 119886 isin 119860 if and only if
119901 (119886 119860) = 119901 (119886 119886) (1)
where 119860 denotes the closure of 119860 with respect to the partialmetric 119901 Note 119860 is closed in (119883 119901) if and only if 119860 = 119860
Definition 4 (see [24]) Two families of self-mappings 119879119894119898
1
and 119878119894119899
1are said to be pairwise commuting if
(1) 119879119894119879119895= 119879119895119879119894 119894 119895 isin 1 2 119898
(2) 119878119896119878119897= 119878119897119878119896 119896 119897 isin 1 2 119899
(3) 119879119894119878119896= 119878119896119879119894 119894 isin 1 2 119898 119896 isin 1 2 119899
Now we recall the following definitions and results from[9]
Let 119862119861119901(119883) be the collection of all nonempty closed and
bounded subsets of119883with respect to the partial metric119901 For119860 isin 119862119861
119901(119883) we define
119901 (119886 119860) = inf 119901 (119886 119909) 119909 isin 119860 (2)
For 119860 119861 isin 119862119861119901(119883)
120575119901(119860 119861) = sup 119901 (119886 119861) 119886 isin 119860
120575119901(119861 119860) = sup 119901 (119887 119860) 119887 isin 119861
(3)
For 119860 119861 isin 119862119861119901(119883)
119867119901(119860 119861) = max 120575
119901(119860 119861) 120575
119901(119861 119860) (4)
Proposition 5 (see [9]) Let (119883 119901) be a partial metric spaceFor any 119860 119861 119862 isin 119862119861
119901(119883) one has
(i) 120575119901(119860 119860) = sup119901(119886 119886) 119886 isin 119860
(ii) 120575119901(119860 119860) le 120575
119901(119860 119861)
(iii) 120575119901(119860 119861) = 0 implies that 119860 sube 119861
(iv) 120575119901(119860 119861) le 120575
119901(119860 119862) + 120575
119901(119862 119861) minus inf
119888isin119862119901(119888 119888)
Proposition 6 (see [9]) Let (119883 119901) be a partial metric spaceFor any 119860 119861 119862 isin 119862119861
119901(119883) one has
(h1) 119867119901(119860 119860) le 119867
119901(119860 119861)
(h2) 119867119901(119860 119861) = 119867
119901(119861 119860)
(h3) 119867119901(119860 119861) le 119867
119901(119860 119862) + 119867
119901(119862 119861) minus inf
119888isin119862119901(119888 119888)
Lemma 7 (see [9]) Let 119860 and 119861 be nonempty closed andbounded subsets of a partial metric space (119883 119901) and ℎ gt 1Then for every 119886 isin 119860 there exists 119887 isin 119861 such that 119901(119886 119887) le
ℎ119867119901(119860 119861)
Lemma 8 (see [10]) Let 119860 and 119861 be nonempty closed andbounded subsets of a partialmetric space (119883 119901) and 0 lt ℎ isin RThen for every 119886 isin 119860 there exists 119887 isin 119861 such that 119901(119886 119887) le
119867119901(119860 119861) + ℎ
2 Results for Single Valued Mappings
The following result regarding the existence of the commonfixed point of themappings satisfying a contractive conditionon the closed ball is very useful in the sense that it requiresthe contractiveness of the mappings only on the closed ballinstead of the whole space
Theorem 9 Let 119878 119879 119883 rarr 119883 be mappings on a completePMS (119883 119901) and 119909
0 119909 119910 isin 119883 and 119903 gt 0 Suppose that there
exist nonnegative reals 120572 120573 and 120574 such that 120572 + 120573 + 2120574 lt 1 If119878 and 119879 satisfy
119901 (119878119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119878119909) 119901 (119910 119879119910) + 120574119901 (119910 119878119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(5)
for all 119909 119910 isin 119861119901(1199090 119903)
119901 (1199090 1198781199090) le (1 minus 120582) (119903 + 119901 (119909
0 1199090)) (6)
where 120582 = (120572+ 120574)(1 minus120573minus 120574) Then there exists a unique point119906 isin 119861119901(1199090 119903) such that 119906 = 119878119906 = 119879119906 Also 119901(119906 119906) = 0
Proof Let 1199090be an arbitrary point in119883 and define
1199092119896+1
= 1198781199092119896 1199092119896+2
= 1198791199092119896+1
where 119896 = 0 1 2
(7)
We will prove that 119909119899
isin (119861(1199090 119903)) for all 119899 isin N by
mathematical induction Using inequality (6) and the factthat 120582 = (120572 + 120574)(1 minus 120573 minus 120574) lt 1 we have
119901 (1199090 1198781199090) le 119903 + 119901 (119909
0 1199090) (8)
It implies that 1199091
isin (119861(1199090 119903)) Let 119909
2 119909
119895isin 119861(119909
0 119903) for
some 119895 isin 119873 If 119895 = 2119896 + 1 where 119896 = 0 1 2 (119895 minus 1)2 sousing inequality (5) we obtain
119901 (1199092119896+1
1199092119896+2
)
= 119901 (1198781199092119896 1198791199092119896+1
)
le 120572119901 (1199092119896 1199092119896+1
)
+ (120573119901 (1199092119896 1198781199092119896) 119901 (119909
2119896+1 1198791199092119896+1
)
+120574119901 (1199092119896+1
1198781199092119896) 119901 (119909
2119896 1198791199092119896+1
))
times (1 + 119901 (1199092119896 1199092119896+1
))minus1
le 120572119901 (1199092119896 1199092119896+1
)
+ (120573119901 (1199092119896 1199092119896+1
) 119901 (1199092119896+1
1199092119896+2
)
+120574119901 (1199092119896+1
1199092119896+1
) 119901 (1199092119896 1199092119896+2
))
times (1 + 119901 (1199092119896 1199092119896+1
))minus1
Abstract and Applied Analysis 3
le 120572119901 (1199092119896 1199092119896+1
)
+ (120573119901 (1199092119896 1199092119896+1
) 119901 (1199092119896+1
1199092119896+2
)
+120574119901 (1199092119896 1199092119896+1
) 119901 (1199092119896 1199092119896+2
))
times (1 + 119901 (1199092119896 1199092119896+1
))minus1
le 120572119901 (1199092119896 1199092119896+1
) + 120573119901 (1199092119896+1
1199092119896+2
) + 120574119901 (1199092119896 1199092119896+2
)
(9)
as 1 + 119901(1199092119896 1199092119896+1
) gt 119901(1199092119896 1199092119896+1
) and so
119901 (1199092119896+1
1199092119896+2
) le (120572 + 120574
1 minus 120573 minus 120574)119901 (119909
2119896 1199092119896+1
) (10)
which implies that
119901 (1199092119896+1
1199092119896+2
) le 120582119901 (1199092119896 1199092119896+1
) le sdot sdot sdot le 1205822119896+1
119901 (1199090 1199091)
(11)
If 119895 = 2119896 + 2 where 119896 = 0 1 2 (119895 minus 2)2 one can easilyprove that
119901 (1199092119896+2
1199092119896+3
) le 1205822119896+2
119901 (1199090 1199091) (12)
Thus from inequality (11) and (12) we have
119901 (119909119895 119909119895+1
) le 120582119895119901 (1199090 1199091) for some 119895 isin 119873 (13)
Now
119901 (1199090 119909119895+1
) le 119901 (1199090 1199091) + sdot sdot sdot + 119901 (119909
119895 119909119895+1
)
minus [119901 (1199091 1199091) + sdot sdot sdot + 119901 (119909
119895 119909119895)]
le 119901 (1199090 1199091) + sdot sdot sdot + 120582
119895119901 (1199090 1199091)
= 119901 (1199090 1199091) [1 + sdot sdot sdot + 120582
119895minus1+ 120582119895]
le (1 minus 120582) [119903 + 119901 (1199090 1199090)]
(1 minus 120582119895+1
)
1 minus 120582
le 119903 + 119901 (1199090 1199090)
(14)
gives 119909119895+1
isin 119861(1199090 119903) Hence 119909
119899isin 119861(119909
0 119903) for all 119899 isin N One
can easily prove that
119901 (119909119899 119909119899+1
) le 120582119899119901 (1199090 1199091) (13
lowast)
for all 119899 isin N We now show that 119909119899 is a Cauchy sequence
Without loss of generality assume that 119898 gt 119899 Then using(13lowast) and the triangle inequality for partial metrics (P
4) we
have119901 (119909119899 119909119898) le 119901 (119909
119899 119909119899+1
) + 119901 (119909119899+1
119909119898) minus 119901 (119909
119899+1 119909119899+1
)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119898)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119899+2
) + 119901 (119909119899+2
119909119898)
minus 119901 (119909119899+2
119909119899+2
)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119899+2
) + 119901 (119909119899+2
119909119898)
(15)
Inductively we have
0 le 119901 (119909119899 119909119898)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119899+2
) + sdot sdot sdot + 119901 (119909119898minus1
119909119898)
le 120582119899119901 (1199090 1199091) + 120582119899+1
119901 (1199090 1199091) + sdot sdot sdot + 120582
119898minus1119901 (1199090 1199091)
le (120582119899+ 120582119899+1
+ sdot sdot sdot + 120582119898minus1
) 119901 (1199090 1199091)
le (120582119899
1 minus 120582)119901 (119909
0 1199091)
997888rarr 0 as 119899 997888rarr infin (since 0 lt 120582 lt 1)
(16)
Thus
lim119899rarr+infin
119901 (119909119899 119909119898) = 0 (17)
By the definition of 119901119904 we get for any119898 isin Nlowast
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (18)
Hence the sequence 119909119899 is a Cauchy sequence in
(119861(1199090 119903) 119901119904) By Lemma 2(4) 119909
119899 is a Cauchy sequence in
(119861(1199090 119903) 119901) Therefore there exists a point 119906 isin 119861(119909
0 119903) with
lim119899rarrinfin
119909119899
= 119906 Also lim119899rarrinfin
119901119904(119909119899 119906) = 0 Again from
Lemma 2(4) we have
119901 (119906 119906) = lim119899rarr+infin
119901 (119909119899 119906) = lim
119899rarr+infin119901 (119909119899 119909119898) = 0
(19)
By the triangle inequality (P4) we have
119901 (119906 119878119906) le 119901 (119906 1199092119899+2
) + 119901 (1199092119899+2
119878119906) minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (119906 1199092119899+2
) + 119901 (1198791199092119899+1
119878119906)
le 119901 (119906 1199092119899+2
) + 120572119901 (1199092119899+1
119906)
+ (120573119901 (1199092119899+1
1198791199092119899+1
) 119901 (119906 119878119906)
+120574119901 (119906 1198791199092119899+1
) 119901 (1199092119899+1
119878119906))
times (1 + 119901 (1199092119899+1
119906))minus1
le 119901 (119906 1199092119899+2
) + 120572119901 (1199092119899+1
119906)
+ (120573119901 (1199092119899+1
1199092119899+2
) 119901 (119906 119878119906)
+120574119901 (119906 1199092119899+2
) 119901 (1199092119899+1
119878119906))
times (1 + 119901 (1199092119899+1
119906))minus1
(20)
Letting 119899 rarr +infin and using (19) we obtain
119901 (119906 119878119906) = 0 (21)
By (P1) we concluded that 119906 = 119878119906 It follows similarly that
119906 = 119879119906 To prove the uniqueness of common fixed point let
4 Abstract and Applied Analysis
119906lowastisin 119861(119909
0 119903) be another common fixed point of 119878 and119879 that
is 119906lowast = 119878119906lowast= 119879119906lowast Then
119901 (119906 119906lowast) = 119901 (119878119906 119879119906
lowast)
le 120572119901 (119906 119906lowast)
+120573119901 (119906 119878119906) 119901 (119906
lowast 119879119906lowast)+120574119901 (119906
lowast 119878119906) 119901 (119906 119879119906
lowast)
1+119901 (119906 119906lowast)
= 120572119901 (119906 119906lowast) +
120574119901 (119906lowast 119906) 119901 (119906 119906
lowast)
1 + 119901 (119906 119906lowast)
(22)
so that119901(119906 119906lowast) le 120572119901(119906 119906lowast)+120574119901(119906 119906
lowast) because 1+119901(119906 119906
lowast) gt
119901(119906 119906lowast) Therefore 119901(119906 119906
lowast) le (120572 + 120574)119901(119906 119906
lowast) which is a
contradiction so that 119906 = 119906lowast (as 120572 + 120574 lt 1) Hence 119878 and
119879 have a unique common fixed point in 119861(1199090 119903)
Example 10 Let119883 = [0 +infin) endowed with the usual partialmetric 119901 defined by 119901 119883 times 119883 rarr R+ with 119901(119909 119910) =
max119909 119910 Clearly (119883 119901) is a partial metric space Now wedefine 119878 119879 119883 rarr 119883 as
119878 (119909) =
119909
16if 0 le 119909 le 1
119909 minus1
6if 119909 gt 1
119879 (119909) =
5119909
17if 0 le 119909 le 1
119909 minus1
7if 119909 gt 1
(23)
for all 119909 isin 119883 Taking 120572 = 15 120573 = 16 120574 = 18 1199090= 12
and 119903 = 12 then 119861119901(1199090 119903) = [0 1] Also we have 119901(119909
0 1199090) =
max12 12 = 12 120582 = (120572 + 120574)(1 minus 120573 minus 120574) = 3985 with
(1 minus 120582) (119903 + 119901 (1199090 1199090)) =
46
85
119901 (1199090 1198781199090) = 119901 (
1
21
32) =
1
2lt (1 minus 120582) (119903 + 119901 (119909
0 1199090))
(24)
Also if 119909 119910 isin (1 +infin) then
119901 (119878119909 119879119910) = max 119909 minus1
6 119909 minus
1
7 ge
1
5max 119909 119910
+ (1
6max 119909 119909 minus
1
6max 119910 119910 minus
1
7
+1
8max 119910 119909 minus
1
6max 119909 119910 minus
1
7)
times (1 +max 119909 119910)minus1
= 120572119901 (119909 119910)
+120573119901 (119909 119878119909) 119901 (119910 119879119910) + 120574119901 (119910 119878119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(25)
So the contractive condition does not hold on whole of 119883Now if 119909 119910 isin 119861
119901(1199090 119903) then
119901 (119878119909 119879119910) = max 119909
165119910
17 le
1
5max 119909 119910
+ (1
6max 119909 119909 minus
1
6max 119910 119910 minus
1
7
+1
8max 119910 119909 minus
1
6max 119909 119910 minus
1
7)
times (1 +max 119909 119910)minus1
(26)
Therefore all the conditions of Theorem 9 are satisfied Thus0 is the common fixed point of 119878 and 119879 and 119901(0 0) = 0Moreover note that for any metric 119889 on119883
119889 (1198781 1198791) = 119889 (1
165
17) gt
1
5119889 (1 1)
+ (1
6119889 (1
1
16) 119889 (1
5
17)
+1
8119889 (1
1
16) 119889 (1
5
17))
times (1 + 119889 (1 1))minus1
(27)
Therefore commonfixed points of 119878 and119879 cannot be obtainedfrom a metric fixed point theorem
Corollary 11 Let 119878 119879 119883 rarr 119883 be mappings on a completePMS (119883 119901) Suppose that there exist nonnegative reals 120572 120573and 120574 such that 120572 + 120573 + 2120574 lt 1 If 119878 and 119879 satisfy
119901 (119878119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119878119909) 119901 (119910 119879119910) + 120574119901 (119910 119878119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(28)
for all 119909 119910 isin 119883 Then there exists a unique point 119906 isin 119883 suchthat 119906 = 119878119906 = 119879119906 Also 119901(119906 119906) = 0 Further 119878 and 119879 have nofixed point other than 119906
By choosing 120573 = 120574 = 0 in Corollary 11 we get thefollowing corollary
Corollary 12 Let 119878 119879 119883 rarr 119883 be a mappings on completePMS (119883 119901) If 119878 and 119879 satisfy
119901 (119878119909 119879119910) le 120572119901 (119909 119910) (29)
for all 119909 119910 isin 119883 120572 lt 1 (120572 is a nonnegative real) Then 119878 and 119879
have a common fixed point 119906 isin 119883 and 119901(119906 119906) = 0
Remark 13 If we impose Banach type contractive conditionfor a pair 119878 119879 119883 rarr 119883 of mappings on a metric space(119883 119889) that is 119889(119878119909 119879119910) le 120572119889(119909 119910) for all 119909 119910 isin 119883 andthen it follows that 119878119909 = 119879119909 for all 119909 isin 119883 (ie 119878 and 119879 are
Abstract and Applied Analysis 5
equal) Therefore the above condition fails to find commonfixed points of 119878 and 119879 This can be seen as
119889 (1198781 1198791) = 119889 ((1
16) (
5
17)) gt 120572119889 (1 1) = 0 (30)
However the same condition in partial metric space does notassert that 119878 = 119879 This can be seen as by taking the partialmetric same as in Example 10
119901 (1198781 1198791) = 119901 ((1
16) (
5
17)) =
5
17le 120572119901 (1 1) = 120572 (1)
(31)
for any 120572 ge 13 Hence Corollary 12 cannot be obtained froma metric fixed point theorem
Remark 14 By equating 120572 120573 120574 to 0 in all possible combi-nations one can derive a host of corollaries which includeMatthews theorem for mappings defined on a completepartial metric space
By taking 119878 = 119879 in the Theorem 9 we get the followingcorollary
Corollary 15 Let 119879 119883 rarr 119883 be a mapping on a completePMS (119883 119901) and 119909
0 119909 119910 isin 119883 and 119903 gt 0 Suppose that there
exist nonnegative reals 120572 120573 and 120574 such that 120572 + 120573 + 2120574 lt 1 If119879 satisfies
119901 (119879119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119879119909) 119901 (119910 119879119910) + 120574119901 (119910 119879119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(32)
for all 119909 119910 isin 119861119901(1199090 119903)
119901 (1199090 1198791199090) le (1 minus 120582) (119903 + 119901 (119909
0 1199090)) (33)
where 120582 = (120572+ 120574)(1 minus120573minus 120574) Then there exists a unique point119906 isin 119861
119901(1199090 119903) such that 119906 = 119879119906 Also 119901(119906 119906) = 0 Further 119879
has no fixed point other than 119906
By taking 119878 = 119879 in Corollary 11 we get the followingcorollary
Corollary 16 Let 119879 119883 rarr 119883 be a mapping on a completePMS (119883 119901) Suppose that there exist nonnegative reals 120572 120573and 120574 such that 120572 + 120573 + 2120574 lt 1 If 119879 satisfies
119901 (119879119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119879119909) 119901 (119910 119879119910) + 120574119901 (119910 119879119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(34)
for all 119909 119910 isin 119883 Then there exists a unique point 119906 isin 119883 suchthat 119906 = 119879119906 Also 119901(119906 119906) = 0 Further 119879 has no fixed pointother than 119906
Now we give an example in favour of Corollary 16
Example 17 Let 119883 = [0 4] endowed with the usual partialmetric 119901 defined by 119901(119909 119910) = max119909 119910 Clearly (119883 119901) is acomplete partial metric space Now we define 119865 119883 rarr 119883 asfollows
119865 (119909) =
119909
3if 0 le 119909 lt 2
119909
1 + 119909if 2 le 119909 le 4
(35)
for all 119909 isin 119883 Now let 119910 le 119909 If 119909 isin [0 2) (and so 119910 isin [0 2))Then 119901(119865119909 119865119910) = 1199093 119901(119909 119910) = 119909 119901(119909 119865119909) = 119909 119901(119910 119865119910) =
119910 119901(119910 119865119909) = 1199093 119901(119909 119865119910) = 119909 Taking 120572 = 13 120573 = 115120574 = 215 we can prove that all the conditions of Corollary 16are satisfied Now if 119909 isin [2 4] then 119901(119865119909 119865119910) = 119909(1 + 119909)119901(119909 119910) = 119909 119901(119909 119865119909) = 119909 119901(119910 119865119910) = 119910 119901(119910 119865119909) = 119909(1+119909)119901(119909 119865119910) = 119909 and taking 120572 = 13 120573 = 115 120574 = 215 onecan verify the condition of the above corollary Thus all theconditions of Corollary 16 are satisfied and 119906 = 0 is a fixedpoint of the mapping 119865
As an application of Theorem 9 we prove the followingtheorem for two finite families of mappings
Theorem 18 If 119879119894119898
1and 119878
119894119899
1are two pairwise commuting
finite families of self-mapping defined on a complete partialmetric space (119883 119901) such that the mappings 119878 and 119879 (with119879 = 119879
11198792sdot sdot sdot 119879119898and 119878 = 119878
11198782sdot sdot sdot 119878119899) satisfy the contractive
condition (5) then the component maps of the two families119879119894119898
1and 119878
119894119899
1have a unique common fixed point
Proof FromTheorem 9 we can say that the mappings 119879 and119878 have a unique common fixed point 119911 that is 119879119911 = 119878119911 = 119911Now our requirement is to show that 119911 is a common fixedpoint of all the component mappings of both the families Inviewof pairwise commutativity of the families 119879
119894119898
1and 119878
119894119899
1
(for every 1 le 119896 le 119898) we can write 119879119896119911 = 119879
119896119879119911 = 119879119879
119896119911 and
119879119896119911 = 119879119896119878119911 = 119878119879
119896119911 which show that 119879
119896119911 (for every 119896) is also
a common fixed point of 119879 and 119878 By using the uniqueness ofcommonfixed point we canwrite119879
119896119911 = 119911 (for every 119896) which
shows that 119911 is a common fixed point of the family 119879119894119898
1
Using the same argument one can also show that (for every1 le 119896 le 119899) 119878
119896119911 = 119911Thus componentmaps of the two families
119879119894119898
1and 119878
119894119899
1have a unique common fixed point
By setting 1198791= 1198792= sdot sdot sdot = 119879
119898= 119865 and 119878
1= 1198782= sdot sdot sdot =
119878119899= 119866 in Theorem 18 we get the following corollary
Corollary 19 Let 119865 119866 119883 rarr 119883 be two commuting self-mappings defined on a complete PMS (119883 119901) satisfying thecondition
119901 (119865119898119909 119866119899119910)
le 120572119901 (119909 119910)
+120573119901 (119909 119865
119898119909) 119901 (119910 119866
119899119910) + 120574119901 (119910 119865
119898119909) 119901 (119909 119866
119899119910)
1 + 119901 (119909 119910)
(36)
6 Abstract and Applied Analysis
for all 119909 119910 isin 119883 120572 + 120573 + 2120574 lt 1 (120572 120573 and 120574 are nonnegativereals) Then F and G have a unique common fixed point
By setting 119898 = 119899 and 119865 = 119866 = 119879 in Corollary 19 wededuce the following corollary
Corollary 20 Let 119879 119883 rarr 119883 be a mapping defined on acomplete PMS (119883 119901) satisfying the condition
119901 (119879119899119909 119879119899119910)
le 120572119901 (119909 119910)
+120573119901 (119909 119879
119899119909) 119901 (119910 119879
119899119910) + 120574119901 (119910 119879
119899119909) 119901 (119909 119879
119899119910)
1 + 119901 (119909 119910)
(37)
for all 119909 119910 isin 119883 120572 + 120573 + 2120574 lt 1 (120572 120573 and 120574 are nonnegativereals) Then F has a unique fixed point
By setting 120573 = 120574 = 0 we draw following corollary whichcan be viewed as an extension of Bryantrsquos theorem [15] for amapping on a complete PMS (119883 119901)
Corollary 21 Let 119865 119883 rarr 119883 be a mapping on a completePMS (119883 119901) If 119865 satisfies
119901 (119865119899119909 119865119899119910) le 120572119901 (119909 119910) (38)
for all 119909 119910 isin 119883 120572 lt 1 Then 119865 has a unique fixed point
The following example demonstrates the superiority ofBryantrsquos theorem overMatthews theorem on complete partialmetric space
Example 22 Let119883 = [0 4] Define the partial metric 119901 119883 times
119883 rarr R by
119901 (119909 119910) = max 119909 119910 (39)
Then (119883 119901) is a complete partial metric space Let 119865 119883 rarr
119883 be defined as follows
119865 (119909) =
1199092 if 119909 isin [0 1 [
2 if 119909 isin [1 2 [
0 if 119909 isin [2 4]
(40)
Then for 119909 = 0 and 119910 = 1 we get
119901 (119865 (0) 119865 (1)) = 119901 (0 2) = 2 gt 120572119901 (0 1) = 120572 (1) (41)
because 0 le 120572 lt 1 However 1198652 satisfies the requirement ofBryantrsquos theorem and 119911 = 0 is the unique fixed point of 119865
3 Results for Set Valued Mappings
Theorem23 Let (119883 119901) be a complete partial metric space andlet 119878 119879 119883 rarr 119862119861
119901(119883) be mappings such that
119867119901(119878119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119878119909) 119901 (119910 119879119910) + 120574119901 (119910 119878119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(42)
for all 119909 119910 isin 119883 0 le 120572 120573 120574 with 120572 + 120573 + 2120574 lt 1 Then 119878 and 119879
have a common fixed point
Proof Assume that119872 = ((120572 + 120574)(1 minus 120573 minus 120574)) Let 1199090isin 119883 be
arbitrary but fixed element of 119883 and choose 1199091
isin 119878(1199090) By
Lemma 8 we can choose 1199092isin 119879(119909
1) such that
119901 (1199091 1199092) le 119867
119901(119878 (1199090) 119879 (119909
1)) + (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1198781199090) 119901 (119909
1 1198791199091)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199091 1198781199090) 119901 (119909
0 1198791199091)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1199091) 119901 (119909
1 1199092)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199091 1199091) 119901 (119909
0 1199092)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1199091) 119901 (119909
1 1199092)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199090 1199091) 119901 (119909
0 1199092)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573119901 (119909
1 1199092) + 120574119901 (119909
0 1199092)
+ (120572 + 120574)
(43)
So we get
119901 (1199091 1199092) le (
120572 + 120574
1 minus 120573 minus 120574)119901 (119909
0 1199091) + (
120572 + 120574
1 minus 120573 minus 120574) (44)
Since119872 = ((120572 + 120574)(1 minus 120573 minus 120574)) so it further implies that119901 (1199091 1199092) le 119872119901 (119909
0 1199091) + 119872 (45)
By Lemma 8 we can choose 1199093isin 119878(1199092) such that
119901 (1199092 1199093) le 119867
119901(119879 (1199091) 119878 (119909
2)) +
(120572 + 120574)2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1198791199091) 119901 (119909
2 1198781199092)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199092 1198791199091) 119901 (119909
1 1198781199092)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199092 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199091 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
Abstract and Applied Analysis 7
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199091 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573119901 (119909
2 1199093) + 120574119901 (119909
1 1199093)
+(120572 + 120574)
2
1 minus 120573 minus 120574
(46)
So we get
119901 (1199092 1199093) le (
120572 + 120574
1 minus 120573 minus 120574)
2
119901 (1199090 1199091) + 2(
120572 + 120574
1 minus 120573 minus 120574)
2
(47)
Continuing in this manner one can obtain a sequence 119909119899 in
119883 as 1199092119899+1
isin 119878(1199092119899) and 119909
2119899+2isin 119879(119909
2119899+1) such that
119901 (119909119899 119909119899+1
) le 119872119901 (119909119899minus1
119909119899) + 119872
le sdot sdot sdot le 119872119899119901 (1199090 1199091) + 119899119872
119899
(48)
where 119872 = ((120572 + 120573)(1 minus 120572)) lt 1 for all 119899 ge 0 Without lossof generality assume that 119899 gt 119898 Then using (48) and thetriangle inequality for partial metrics (P
4) we have
119901 (119909119899 119909119898)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119899+2
) + sdot sdot sdot + 119901 (119909119898minus1
119909119898)
le 119872119899119901 (1199090 1199091) + 119899119872
119899+ 119872119899+1
119901 (1199090 1199091)
+ (119899 + 1)119872119899+1
+ sdot sdot sdot + 119872119898minus1
119901 (1199090 1199091)
+ (119898 minus 1)119872119898minus1
le
119898minus1
sum
119894=119899
119872119894119901 (1199090 1199091)
+
119898minus1
sum
119894=119899
119894119872119894997888rarr 0 as 119899 997888rarr +infin (since 0 lt 119872 lt 1)
(49)
By the definition of 119901119904 we get
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (50)
This yields that 119909119899 is a Cauchy sequence in (119883 119901
119904) Since
(119883 119901) is complete then from Lemma 2(4) (119883 119901119904) is a com-
plete metric space Therefore the sequence 119909119899 converges
to some 119909lowast
isin 119883 with respect to the metric 119901119904 that is
lim119899rarr+infin
119901119904(119909119899 119909lowast) = 0 Again from Lemma 2(4) we get
119901 (119909lowast 119909lowast) = lim119899rarr+infin
119901 (119909119899 119909lowast) = lim119899rarr+infin
119901 (119909119899 119909119899) = 0 (51)
119867119901(119879 (1199092119899+2
) 119878 (119909lowast))
le 120572119901 (1199092119899+2
119909lowast)
+ 120573119901 (1199092119899+2
119879 (1199092119899+2
)) 119901 (119909lowast 119878 (119909lowast))
1 + 119901 (1199092119899+2
119909lowast)
+ 120574119901 (1199092119899+2
119878 (119909lowast)) 119901 (119909
lowast 119879 (1199092119899+2
))
1 + 119901 (1199092119899+2
119909lowast)
le 120572119901 (1199092119899+2
119909lowast)
+ 120573119901 (1199092119899+2
1199092119899+3
) 119901 (119909lowast 119878 (119909lowast))
1 + 119901 (1199092119899+2
119909lowast)
+ 120574119901 (1199092119899+2
119878 (119909lowast)) 119901 (119909
lowast 1199092119899+1
)
1 + 119901 (1199092119899+2
119909lowast)
(52)
taking limit as 119899 rarr infin and using (51) we get
lim119899rarr+infin
119867119901(119879 (1199092119899+2
) 119878 (119909lowast)) = 0 (53)
Now 1199092119899+1
isin 119879(1199092119899+2
) gives that
119901 (1199092119899+1
119878 (119909lowast)) le 119867
119901(119879 (1199092119899+2
) 119878 (119909lowast)) (54)
which implies that
lim119899rarr+infin
119901 (1199092119899+1
119878 (119909lowast)) = 0 (55)
On the other hand by (P4) we have
119901 (119909lowast 119878 (119909lowast)) le 119901 (119909
lowast 1199092119899+2
) + 119901 (1199092119899+2
119878 (119909lowast))
minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (119909lowast 1199092119899+2
) + 119901 (1199092119899+2
119878 (119909lowast))
(56)
Taking limit as 119899 rarr +infin and using (51) and (55) we obtain119901(119909lowast 119878(119909lowast)) = 0 Therefore from (51) (119901(119909lowast 119909lowast) = 0) we
obtain
119901 (119909lowast 119878 (119909lowast)) = 119901 (119909
lowast 119909lowast) (57)
which from Remark 14 implies that 119909lowast
isin 119878(119909lowast) = 119878(119909lowast)
Similarly one can easily prove that 119909lowast isin 119879(119909lowast) Thus 119878 and
119879 have a common fixed point
Remark 24 For 120573 = 120574 = 0 and 119878 = 119879 Theorem 23 reduces tothe following result of Aydi et al [9]
Corollary 25 (see [9 Theorem 32]) Let (119883 119901) be a partialmetric space If 119879 119883 rarr 119862119861
119901(119883) is a multivalued mapping
such that for all 119909 119910 isin 119883 one has
119867119901(119879119909 119879119910) le 119896119901 (119886 119887) (58)
where 119896 isin (0 1) Then 119879 has a fixed point
8 Abstract and Applied Analysis
Theorem26 Let (119883 119901) be a complete partialmetric space and119878 119879 119883 rarr 119862119861
119901(119883) be multivalued mappings such that
119867119901(119878119909 119879119910) le 120572
119901 (119909 119878119909) 119901 (119909 119879119910) + 119901 (119910 119879119910) 119901 (119910 119878119909)
119901 (119909 119879119910) + 119901 (119910 119878119909)
+ 120573119889 (119909 119910)
(59)
for all 119909 119910 isin 119883 0 le 120572 120573 with 2120572 + 120573 lt 1 and 119901(119909 119879119910) +
119901(119910 119878119909) = 0 Then 119878 and 119879 have a common fixed point
Proof Assume that 119897 = (120572+120573)(1minus120572) Let 1199090isin 119883 be arbitrary
but fixed element of119883 and choose 1199091isin 119878(1199090)
When 119901(119909 119879119910)+119901(119910 119878119909) = 0 By Lemma 8we can choose1199092isin 119879(119909
1) such that
119901 (1199091 1199092)
le 119867119901(119878 (1199090) 119879 (119909
1)) + (120572 + 120573)
le 120572119901 (1199090 1198781199090) 119901 (119909
0 1198791199091) + 119901 (119909
1 1198791199091) 119901 (119909
1 1198781199090)
119901 (1199090 1198791199091) + 119901 (119909
1 1198781199090)
+ 120573119901 (1199090 1199091) + (120572 + 120573)
le 120572119901 (1199090 1199091) 119901 (119909
0 1199092) + 119901 (119909
1 1199092) 119901 (119909
1 1199091)
119901 (1199090 1199092) + 119901 (119909
1 1199091)
+ 120573119901 (1199090 1199091) + (120572 + 120573)
le 120572 119901 (1199090 1199091) + 119901 (119909
1 1199092) + 120573119901 (119909
0 1199091) + (120572 + 120573)
(60)
because 119901(1199090 1199092) lt 119901(119909
0 1199092) + 119901(119909
1 1199091) and 119901(119909
1 1199091) lt
119901(1199091 1199091) + 119901(119909
0 1199092) Thus we get
119901 (1199091 1199092) le (
120572 + 120573
1 minus 120572)119901 (119909
0 1199091) + (
120572 + 120573
1 minus 120572) (61)
It further implies that
119901 (1199091 1199092) le 119897119901 (119909
0 1199091) + 119897 (62)
By Lemma 8 we can choose 1199093isin 119878(1199092) such that
119901 (1199092 1199093)
le 119867119901(119879 (1199091) 119878 (119909
2)) +
(120572 + 120573)2
1 minus 120572
le 120572119901 (1199091 1198791199091) 119901 (119909
1 1198781199092) + 119901 (119909
2 1198781199092) 119901 (119909
2 1198791199091)
119901 (1199091 1198781199092) + 119901 (119909
2 1198791199091)
+ 120573119901 (1199091 1199092) +
(120572 + 120573)2
1 minus 120572
le 120572119901 (1199091 1199092) 119901 (119909
1 1199093) + 119901 (119909
2 1199093) 119901 (119909
2 1199092)
119901 (1199091 1199093) + 119901 (119909
2 1199092)
+ 120573119901 (1199091 1199092) +
(120572 + 120573)2
1 minus 120572
le 120572 119901 (1199091 1199092) + 119901 (119909
2 1199093) + 120573119901 (119909
1 1199092) +
(120572 + 120573)2
1 minus 120572
(63)
because 119901(1199091 1199093) lt 119901(119909
1 1199093) + 119901(119909
2 1199092) and 119901(119909
2 1199092) lt
119901(1199092 1199092) + 119901(119909
1 1199093) Thus we get
119901 (1199092 1199093) le (
120572 + 120573
1 minus 120572)119901 (119909
1 1199092) + (
120572 + 120573
1 minus 120572)
2
(64)
It further implies that
119901 (1199092 1199093) le 1198972119901 (1199090 1199090) + 21198972 (65)
Continuing in this manner one can obtain a sequence 119909119899 in
119883 as 1199092119899+1
isin 119878(1199092119899) and 119909
2119899+2isin 119879(119909
2119899+1) such that
119901 (119909119899 119909119899+1
) le 119897119901 (119909119899minus1
119909119899) + 119897 le sdot sdot sdot le 119897
119899119901 (1199090 1199091) + 119899119897119899
(66)
where 119897 = ((120572 + 120573)(1 minus 120572)) lt 1 for all 119899 ge 0 Withoutloss of generality assume that 119898 gt 119899 Then using (66) andthe triangle inequality for partial metrics (P
4) one can easily
prove that
119901 (119909119899 119909119898) le
119898minus1
sum
119894=119899
119897119894119901 (1199090 1199091) +
119898minus1
sum
119894=119899
119894119897119894
997888rarr 0 as 119899 997888rarr +infin (since 0 lt 119897 lt 1)
(67)
By the definition of 119901119904
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (68)
This yields that 119909119899 is a Cauchy sequence in (119883 119901
119904) Since
(119883 119901) is complete then from Lemma 2(4) (119883 119901119904) is a com-
plete metric space Therefore the sequence 119909119899 converges
to some 1199091015840
isin 119883 with respect to the metric 119901119904 that is
lim119899rarr+infin
119901119904(119909119899 1199091015840) = 0 Again from Lemma 2(4) we get
119901 (1199091015840 1199091015840) = lim119899rarr+infin
119901 (119909119899 119909) = lim119899rarr+infin
119901 (119909119899 119909119899) = 0
(69)
Abstract and Applied Analysis 9
119867119901(119879 (1199092119899+1
) 119878 (1199091015840))
le 120572 (119901 (1199092119899+1
119879 (1199092119899+1
)) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 119879 (1199092119899+1
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 119879 (1199092119899+1
)))minus1
+ 120573119901 (1199092119899+1
119909)
le 120572 (119901 ((1199092119899+1
1199092119899+2
) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 1199092119899+2
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 1199092119899+2
))minus1
+ 120573119901 (1199092119899+1
119909)
(70)
therefore
lim119899rarr+infin
119867119901(119879 (1199092119899+1
) 119878 (1199091015840)) = 0 (71)
Now 1199092119899+2
isin 119879(1199092119899+1
) gives that
119901 (1199092119899+2
119878 (1199091015840)) le 119867
119901(119879 (1199092119899+1
) 119878 (1199091015840)) (72)
which implies that
lim119899rarr+infin
119901 (1199092119899+2
119878 (1199091015840)) = 0 (73)
On the other hand we have
119901 (1199091015840 119878 (1199091015840)) le 119901 (119909
1015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (1199091015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
(74)
Taking limit as 119899 rarr +infin and using (69) and (73) we obtain119901(1199091015840 119878(1199091015840)) = 0 Therefore from (69) (119901(1199091015840 1199091015840) = 0) we
obtain
119901 (1199091015840 119878 (1199091015840)) = 119901 (119909
1015840 1199091015840) (75)
which from Remark 14 implies that 1199091015840
isin 119878(1199091015840) = 119878(1199091015840)
It follows similarly that 1199091015840
isin 119879(1199091015840) Thus 119878 and 119879 have a
common fixed point
Now we give an example which illustrates our Theo-rem 26
Example 27 Let 119883 = 1 2 3 be endowed with usual orderand let 119901 be a partial metric on119883 defined as
119901 (1 1) = 119901 (2 2) = 0 119901 (3 3) =5
11
119901 (1 2) = 119901 (2 1) =3
10
119901 (1 3) = 119901 (3 1) =9
20
119901 (2 3) = 119901 (3 2) =1
2
(76)
Define the mappings 119878 119879 119883 rarr 119862119861119901(119883) by
119878119909 = 1 if 119909 119910 isin 1 2
1 2 otherwise
119879119909 = 1 if 119909 119910 isin 1 2
2 otherwise
(77)
Note that 119878119909 and 119879119909 are closed and bounded for all 119909 isin 119883
with respect to the partial metric 119901 To show that for all 119909 119910in119883 (59) is satisfied with 120572 = 111 120573 = 45 we consider thefollowing cases if 119909 119910 isin 1 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 1) = 0 (78)
and condition (59) is satisfied obviously
If 119909 = 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 2) =
3
10
119901 (119909 119878119909) = 119901 (119910 119878119909) = 119901 (3 1 2) =9
20
119901 (119909 119879119910) = 119901 (119910 119879119910) = 119901 (119910 119878119909) = 119901 (3 2) =11
24
119901 (119909 119910) = 119901 (3 3) =5
11
(79)
If 119909 = 3 119910 = 1 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (1 1) = 0 119901 (119910 119878119909) = 119901 (1 1 2) = 0
119901 (119909 119910) = 119901 (3 1) =9
20
(80)
10 Abstract and Applied Analysis
If 119909 = 3 119910 = 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (2 1) =3
10 119901 (119910 119878119909) = 119901 (2 1 2) = 0
119901 (119909 119910) = 119901 (3 2) =1
2
(81)
If 119909 = 1 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (1 1) = 0 119901 (119909 119879119910) = 119901 (1 2) =3
10
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (1 3) =9
20
(82)
If 119909 = 2 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (2 1) =3
10 119901 (119909 119879119910) = 119901 (2 2) = 0
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (2 3) =1
2
(83)
Thus all the conditions ofTheorem 26 are satisfied Here 119909 =
1 is a common fixed point of 119878 and 119879On the other hand the metric 119901
119904 induced by the partialmetric 119901 is given by
119901119904(1 1) = 119901
119904(2 2) = 119901
119904(3 3) = 0
119901119904(2 1) = 119901
119904(2 1) =
3
4
119901119904(3 2) = 119901
119904(2 3) =
4
7
119901119904(3 1) = 119901
119904(1 3) =
14
29
(84)
Note that in case of ordinary Hausdorff metric given map-ping does not satisfy the condition Indeed for 119909 = 1 and119910 = 3 we have
119867(119878119909 119879119910) = 119867 (1 2) =3
4
119901119904(119909 119878119909) = 119901
119904(1 1) = 0
119901119904(119909 119879119910) = 119901
119904(1 2) =
3
4
119901119904(119910 119879119910) = 119901
119904(3 2) =
4
7
119901119904(119910 119878119909) = 119901
119904(3 1) =
14
29
(85)
for the values of 120572 = 111 120573 = 45 By a routine calculationone can easily verify that the mapping does not satisfy thecondition which involved ordinary Hausdorff metric
Acknowledgment
This paper was funded by the Deanship of Scientific Research(DSR) King Abdulaziz University Jeddah The authorstherefore acknowledge with thanks DSR technical and finan-cial support
References
[1] S G Matthews ldquoPartial metric topologyrdquo in Proceedings of the8th Summer Conference on General Topology and Applicationsvol 728 pp 183ndash197 New York Academy of Science 1994
[2] T Abdeljawad E Karapinar andK Tas ldquoA generalized contrac-tion principle with control functions on partial metric spacesrdquoComputers amp Mathematics with Applications vol 63 no 3 pp716ndash719 2012
[3] T Abdeljawad ldquoFixed points for generalized weakly contractivemappings in partialmetric spacesrdquoMathematical andComputerModelling vol 54 no 11-12 pp 2923ndash2927 2011
[4] J Ahmad M Arshad and C Vetro ldquoOn a theorem of Khan in ageneralized metric spacerdquo International Journal of Analysis vol2013 Article ID 852727 6 pages 2013
[5] S Alsulami N Hussain and A Alotaibi ldquoCoupled fixed andcoincidence points for monotone operators in partial metricspacesrdquo Fixed Point Theory and Applications vol 2012 article173 2012
[6] I Altun and A Erduran ldquoFixed point theorems for monotonemappings on partial metric spacesrdquo Fixed Point Theory andApplications vol 2011 Article ID 508730 2011
[7] M Arshad J Ahmad and E Karapinar ldquoSome common fixedpoint results in rectangularmetric spacesrdquo International Journalof Analysis vol 2013 Article ID 307234 7 pages 2013
[8] M Arshad E Karapinar and J Ahmad ldquoSome unique fixedpoint theorem for rational contractions in partially orderedmetric spacesrdquo Journal of Inequalities andApplications vol 2013article 248 2013
[9] H Aydi M Abbas and C Vetro ldquoPartial Hausdorff metric andNadlerrsquos fixed point theorem on partial metric spacesrdquo Topologyand Its Applications vol 159 no 14 pp 3234ndash3242 2012
Abstract and Applied Analysis 11
[10] H Aydi M Abbas and C Vetro ldquoCommon Fixed points formultivalued generalized contractions on partial metric spacesrdquoRevista de la Real Academia de Ciencias Exactas Fisicas yNaturales A 2013
[11] A Azam and M Arshad ldquoFixed points of a sequence of locallycontractive multivalued mapsrdquo Computers amp Mathematics withApplications vol 57 no 1 pp 96ndash100 2009
[12] A Azam B Fisher and M Khan ldquoCommon fixed point the-orems in complex valued metric spacesrdquo Numerical FunctionalAnalysis and Optimization vol 32 no 3 pp 243ndash253 2011
[13] S Banach ldquoSur les operations dans les ensembles abstraitset leurs applications aux equations integralesrdquo FundamentaMathematicae vol 3 pp 133ndash181 1922
[14] I Beg and A Azam ldquoFixed points of asymptotically regularmultivalued mappingsrdquo Journal of the Australian MathematicalSociety A vol 53 no 3 pp 313ndash326 1992
[15] V W Bryant ldquoA remark on a fixed-point theorem for iteratedmappingsrdquo The American Mathematical Monthly vol 75 pp399ndash400 1968
[16] K P Chi E Karapınar and T D Thanh ldquoA generalizedcontraction principle in partial metric spacesrdquo Mathematicaland Computer Modelling vol 55 no 5-6 pp 1673ndash1681 2012
[17] N Hussain H K Nashine Z Kadelburg and S M AlsulamildquoWeakly isotone increasingmappings and endpoints in partiallyordered metric spacesrdquo Journal of Inequalities and Applicationsvol 2012 article 232 2012
[18] NHussain DDJoric Z Kadelburg and S Radenovic ldquoSuzuki-type fixed point results in metric type spacesrdquo Fixed PointTheory and Applications vol 2012 article 126 2012
[19] N Hussain Z Kadelburg S Radenovic and F R Al-SolamyldquoComparison functions and fixed point results in partial metricspacesrdquo Abstract and Applied Analysis vol 2012 Article ID605781 15 pages 2012
[20] N Hussain and M Abbas ldquoCommon fixed point results fortwo new classes of hybrid pairs in symmetric spacesrdquo AppliedMathematics and Computation vol 218 no 2 pp 542ndash547 2011
[21] S Hong ldquoFixed points of multivalued operators in orderedmetric spaces with applicationsrdquo Nonlinear Analysis TheoryMethods amp Applications vol 72 no 11 pp 3929ndash3942 2010
[22] S Hong ldquoFixed points for mixed monotone multivalued oper-ators in Banach spaces with applicationsrdquo Journal of Mathemat-ical Analysis and Applications vol 337 no 1 pp 333ndash342 2008
[23] S Hong ldquoFixed points of discontinuous multivalued increasingoperators in Banach spaces with applicationsrdquo Journal of Math-ematical Analysis and Applications vol 282 no 1 pp 151ndash1622003
[24] M Imdad J Ali and M Tanveer ldquoCoincidence and commonfixed point theorems for nonlinear contractions in Menger PMspacesrdquo Chaos Solitons amp Fractals vol 42 no 5 pp 3121ndash31292009
[25] E Karapinar ldquoCiric type nonunique fixed point theorems onpartial metric spacesrdquo The Journal of Nonlinear Science andApplications vol 5 no 2 pp 74ndash83 2012
[26] E Karapnar and I M Erhan ldquoFixed point theorems for opera-tors on partial metric spacesrdquo Applied Mathematics Letters vol24 no 11 pp 1894ndash1899 2011
[27] E KarapinarMMarudai andV Pragadeeshwarar ldquoFixed pointtheorems for generalized weak contractions satisfying rationalexpressions on ordered Partial Metric Spacerdquo LobachevskiiJournal of Mathematics vol 34 no 1 pp 116ndash123 2013
[28] M S Khan M Swaleh and M Imdad Some Fixed PointTheorems IV Communications 1983
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Differential EquationsInternational Journal of
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Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Algebra
Discrete Dynamics in Nature and Society
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Decision SciencesAdvances in
Discrete MathematicsJournal of
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Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
Abstract and Applied Analysis 3
le 120572119901 (1199092119896 1199092119896+1
)
+ (120573119901 (1199092119896 1199092119896+1
) 119901 (1199092119896+1
1199092119896+2
)
+120574119901 (1199092119896 1199092119896+1
) 119901 (1199092119896 1199092119896+2
))
times (1 + 119901 (1199092119896 1199092119896+1
))minus1
le 120572119901 (1199092119896 1199092119896+1
) + 120573119901 (1199092119896+1
1199092119896+2
) + 120574119901 (1199092119896 1199092119896+2
)
(9)
as 1 + 119901(1199092119896 1199092119896+1
) gt 119901(1199092119896 1199092119896+1
) and so
119901 (1199092119896+1
1199092119896+2
) le (120572 + 120574
1 minus 120573 minus 120574)119901 (119909
2119896 1199092119896+1
) (10)
which implies that
119901 (1199092119896+1
1199092119896+2
) le 120582119901 (1199092119896 1199092119896+1
) le sdot sdot sdot le 1205822119896+1
119901 (1199090 1199091)
(11)
If 119895 = 2119896 + 2 where 119896 = 0 1 2 (119895 minus 2)2 one can easilyprove that
119901 (1199092119896+2
1199092119896+3
) le 1205822119896+2
119901 (1199090 1199091) (12)
Thus from inequality (11) and (12) we have
119901 (119909119895 119909119895+1
) le 120582119895119901 (1199090 1199091) for some 119895 isin 119873 (13)
Now
119901 (1199090 119909119895+1
) le 119901 (1199090 1199091) + sdot sdot sdot + 119901 (119909
119895 119909119895+1
)
minus [119901 (1199091 1199091) + sdot sdot sdot + 119901 (119909
119895 119909119895)]
le 119901 (1199090 1199091) + sdot sdot sdot + 120582
119895119901 (1199090 1199091)
= 119901 (1199090 1199091) [1 + sdot sdot sdot + 120582
119895minus1+ 120582119895]
le (1 minus 120582) [119903 + 119901 (1199090 1199090)]
(1 minus 120582119895+1
)
1 minus 120582
le 119903 + 119901 (1199090 1199090)
(14)
gives 119909119895+1
isin 119861(1199090 119903) Hence 119909
119899isin 119861(119909
0 119903) for all 119899 isin N One
can easily prove that
119901 (119909119899 119909119899+1
) le 120582119899119901 (1199090 1199091) (13
lowast)
for all 119899 isin N We now show that 119909119899 is a Cauchy sequence
Without loss of generality assume that 119898 gt 119899 Then using(13lowast) and the triangle inequality for partial metrics (P
4) we
have119901 (119909119899 119909119898) le 119901 (119909
119899 119909119899+1
) + 119901 (119909119899+1
119909119898) minus 119901 (119909
119899+1 119909119899+1
)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119898)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119899+2
) + 119901 (119909119899+2
119909119898)
minus 119901 (119909119899+2
119909119899+2
)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119899+2
) + 119901 (119909119899+2
119909119898)
(15)
Inductively we have
0 le 119901 (119909119899 119909119898)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119899+2
) + sdot sdot sdot + 119901 (119909119898minus1
119909119898)
le 120582119899119901 (1199090 1199091) + 120582119899+1
119901 (1199090 1199091) + sdot sdot sdot + 120582
119898minus1119901 (1199090 1199091)
le (120582119899+ 120582119899+1
+ sdot sdot sdot + 120582119898minus1
) 119901 (1199090 1199091)
le (120582119899
1 minus 120582)119901 (119909
0 1199091)
997888rarr 0 as 119899 997888rarr infin (since 0 lt 120582 lt 1)
(16)
Thus
lim119899rarr+infin
119901 (119909119899 119909119898) = 0 (17)
By the definition of 119901119904 we get for any119898 isin Nlowast
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (18)
Hence the sequence 119909119899 is a Cauchy sequence in
(119861(1199090 119903) 119901119904) By Lemma 2(4) 119909
119899 is a Cauchy sequence in
(119861(1199090 119903) 119901) Therefore there exists a point 119906 isin 119861(119909
0 119903) with
lim119899rarrinfin
119909119899
= 119906 Also lim119899rarrinfin
119901119904(119909119899 119906) = 0 Again from
Lemma 2(4) we have
119901 (119906 119906) = lim119899rarr+infin
119901 (119909119899 119906) = lim
119899rarr+infin119901 (119909119899 119909119898) = 0
(19)
By the triangle inequality (P4) we have
119901 (119906 119878119906) le 119901 (119906 1199092119899+2
) + 119901 (1199092119899+2
119878119906) minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (119906 1199092119899+2
) + 119901 (1198791199092119899+1
119878119906)
le 119901 (119906 1199092119899+2
) + 120572119901 (1199092119899+1
119906)
+ (120573119901 (1199092119899+1
1198791199092119899+1
) 119901 (119906 119878119906)
+120574119901 (119906 1198791199092119899+1
) 119901 (1199092119899+1
119878119906))
times (1 + 119901 (1199092119899+1
119906))minus1
le 119901 (119906 1199092119899+2
) + 120572119901 (1199092119899+1
119906)
+ (120573119901 (1199092119899+1
1199092119899+2
) 119901 (119906 119878119906)
+120574119901 (119906 1199092119899+2
) 119901 (1199092119899+1
119878119906))
times (1 + 119901 (1199092119899+1
119906))minus1
(20)
Letting 119899 rarr +infin and using (19) we obtain
119901 (119906 119878119906) = 0 (21)
By (P1) we concluded that 119906 = 119878119906 It follows similarly that
119906 = 119879119906 To prove the uniqueness of common fixed point let
4 Abstract and Applied Analysis
119906lowastisin 119861(119909
0 119903) be another common fixed point of 119878 and119879 that
is 119906lowast = 119878119906lowast= 119879119906lowast Then
119901 (119906 119906lowast) = 119901 (119878119906 119879119906
lowast)
le 120572119901 (119906 119906lowast)
+120573119901 (119906 119878119906) 119901 (119906
lowast 119879119906lowast)+120574119901 (119906
lowast 119878119906) 119901 (119906 119879119906
lowast)
1+119901 (119906 119906lowast)
= 120572119901 (119906 119906lowast) +
120574119901 (119906lowast 119906) 119901 (119906 119906
lowast)
1 + 119901 (119906 119906lowast)
(22)
so that119901(119906 119906lowast) le 120572119901(119906 119906lowast)+120574119901(119906 119906
lowast) because 1+119901(119906 119906
lowast) gt
119901(119906 119906lowast) Therefore 119901(119906 119906
lowast) le (120572 + 120574)119901(119906 119906
lowast) which is a
contradiction so that 119906 = 119906lowast (as 120572 + 120574 lt 1) Hence 119878 and
119879 have a unique common fixed point in 119861(1199090 119903)
Example 10 Let119883 = [0 +infin) endowed with the usual partialmetric 119901 defined by 119901 119883 times 119883 rarr R+ with 119901(119909 119910) =
max119909 119910 Clearly (119883 119901) is a partial metric space Now wedefine 119878 119879 119883 rarr 119883 as
119878 (119909) =
119909
16if 0 le 119909 le 1
119909 minus1
6if 119909 gt 1
119879 (119909) =
5119909
17if 0 le 119909 le 1
119909 minus1
7if 119909 gt 1
(23)
for all 119909 isin 119883 Taking 120572 = 15 120573 = 16 120574 = 18 1199090= 12
and 119903 = 12 then 119861119901(1199090 119903) = [0 1] Also we have 119901(119909
0 1199090) =
max12 12 = 12 120582 = (120572 + 120574)(1 minus 120573 minus 120574) = 3985 with
(1 minus 120582) (119903 + 119901 (1199090 1199090)) =
46
85
119901 (1199090 1198781199090) = 119901 (
1
21
32) =
1
2lt (1 minus 120582) (119903 + 119901 (119909
0 1199090))
(24)
Also if 119909 119910 isin (1 +infin) then
119901 (119878119909 119879119910) = max 119909 minus1
6 119909 minus
1
7 ge
1
5max 119909 119910
+ (1
6max 119909 119909 minus
1
6max 119910 119910 minus
1
7
+1
8max 119910 119909 minus
1
6max 119909 119910 minus
1
7)
times (1 +max 119909 119910)minus1
= 120572119901 (119909 119910)
+120573119901 (119909 119878119909) 119901 (119910 119879119910) + 120574119901 (119910 119878119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(25)
So the contractive condition does not hold on whole of 119883Now if 119909 119910 isin 119861
119901(1199090 119903) then
119901 (119878119909 119879119910) = max 119909
165119910
17 le
1
5max 119909 119910
+ (1
6max 119909 119909 minus
1
6max 119910 119910 minus
1
7
+1
8max 119910 119909 minus
1
6max 119909 119910 minus
1
7)
times (1 +max 119909 119910)minus1
(26)
Therefore all the conditions of Theorem 9 are satisfied Thus0 is the common fixed point of 119878 and 119879 and 119901(0 0) = 0Moreover note that for any metric 119889 on119883
119889 (1198781 1198791) = 119889 (1
165
17) gt
1
5119889 (1 1)
+ (1
6119889 (1
1
16) 119889 (1
5
17)
+1
8119889 (1
1
16) 119889 (1
5
17))
times (1 + 119889 (1 1))minus1
(27)
Therefore commonfixed points of 119878 and119879 cannot be obtainedfrom a metric fixed point theorem
Corollary 11 Let 119878 119879 119883 rarr 119883 be mappings on a completePMS (119883 119901) Suppose that there exist nonnegative reals 120572 120573and 120574 such that 120572 + 120573 + 2120574 lt 1 If 119878 and 119879 satisfy
119901 (119878119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119878119909) 119901 (119910 119879119910) + 120574119901 (119910 119878119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(28)
for all 119909 119910 isin 119883 Then there exists a unique point 119906 isin 119883 suchthat 119906 = 119878119906 = 119879119906 Also 119901(119906 119906) = 0 Further 119878 and 119879 have nofixed point other than 119906
By choosing 120573 = 120574 = 0 in Corollary 11 we get thefollowing corollary
Corollary 12 Let 119878 119879 119883 rarr 119883 be a mappings on completePMS (119883 119901) If 119878 and 119879 satisfy
119901 (119878119909 119879119910) le 120572119901 (119909 119910) (29)
for all 119909 119910 isin 119883 120572 lt 1 (120572 is a nonnegative real) Then 119878 and 119879
have a common fixed point 119906 isin 119883 and 119901(119906 119906) = 0
Remark 13 If we impose Banach type contractive conditionfor a pair 119878 119879 119883 rarr 119883 of mappings on a metric space(119883 119889) that is 119889(119878119909 119879119910) le 120572119889(119909 119910) for all 119909 119910 isin 119883 andthen it follows that 119878119909 = 119879119909 for all 119909 isin 119883 (ie 119878 and 119879 are
Abstract and Applied Analysis 5
equal) Therefore the above condition fails to find commonfixed points of 119878 and 119879 This can be seen as
119889 (1198781 1198791) = 119889 ((1
16) (
5
17)) gt 120572119889 (1 1) = 0 (30)
However the same condition in partial metric space does notassert that 119878 = 119879 This can be seen as by taking the partialmetric same as in Example 10
119901 (1198781 1198791) = 119901 ((1
16) (
5
17)) =
5
17le 120572119901 (1 1) = 120572 (1)
(31)
for any 120572 ge 13 Hence Corollary 12 cannot be obtained froma metric fixed point theorem
Remark 14 By equating 120572 120573 120574 to 0 in all possible combi-nations one can derive a host of corollaries which includeMatthews theorem for mappings defined on a completepartial metric space
By taking 119878 = 119879 in the Theorem 9 we get the followingcorollary
Corollary 15 Let 119879 119883 rarr 119883 be a mapping on a completePMS (119883 119901) and 119909
0 119909 119910 isin 119883 and 119903 gt 0 Suppose that there
exist nonnegative reals 120572 120573 and 120574 such that 120572 + 120573 + 2120574 lt 1 If119879 satisfies
119901 (119879119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119879119909) 119901 (119910 119879119910) + 120574119901 (119910 119879119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(32)
for all 119909 119910 isin 119861119901(1199090 119903)
119901 (1199090 1198791199090) le (1 minus 120582) (119903 + 119901 (119909
0 1199090)) (33)
where 120582 = (120572+ 120574)(1 minus120573minus 120574) Then there exists a unique point119906 isin 119861
119901(1199090 119903) such that 119906 = 119879119906 Also 119901(119906 119906) = 0 Further 119879
has no fixed point other than 119906
By taking 119878 = 119879 in Corollary 11 we get the followingcorollary
Corollary 16 Let 119879 119883 rarr 119883 be a mapping on a completePMS (119883 119901) Suppose that there exist nonnegative reals 120572 120573and 120574 such that 120572 + 120573 + 2120574 lt 1 If 119879 satisfies
119901 (119879119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119879119909) 119901 (119910 119879119910) + 120574119901 (119910 119879119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(34)
for all 119909 119910 isin 119883 Then there exists a unique point 119906 isin 119883 suchthat 119906 = 119879119906 Also 119901(119906 119906) = 0 Further 119879 has no fixed pointother than 119906
Now we give an example in favour of Corollary 16
Example 17 Let 119883 = [0 4] endowed with the usual partialmetric 119901 defined by 119901(119909 119910) = max119909 119910 Clearly (119883 119901) is acomplete partial metric space Now we define 119865 119883 rarr 119883 asfollows
119865 (119909) =
119909
3if 0 le 119909 lt 2
119909
1 + 119909if 2 le 119909 le 4
(35)
for all 119909 isin 119883 Now let 119910 le 119909 If 119909 isin [0 2) (and so 119910 isin [0 2))Then 119901(119865119909 119865119910) = 1199093 119901(119909 119910) = 119909 119901(119909 119865119909) = 119909 119901(119910 119865119910) =
119910 119901(119910 119865119909) = 1199093 119901(119909 119865119910) = 119909 Taking 120572 = 13 120573 = 115120574 = 215 we can prove that all the conditions of Corollary 16are satisfied Now if 119909 isin [2 4] then 119901(119865119909 119865119910) = 119909(1 + 119909)119901(119909 119910) = 119909 119901(119909 119865119909) = 119909 119901(119910 119865119910) = 119910 119901(119910 119865119909) = 119909(1+119909)119901(119909 119865119910) = 119909 and taking 120572 = 13 120573 = 115 120574 = 215 onecan verify the condition of the above corollary Thus all theconditions of Corollary 16 are satisfied and 119906 = 0 is a fixedpoint of the mapping 119865
As an application of Theorem 9 we prove the followingtheorem for two finite families of mappings
Theorem 18 If 119879119894119898
1and 119878
119894119899
1are two pairwise commuting
finite families of self-mapping defined on a complete partialmetric space (119883 119901) such that the mappings 119878 and 119879 (with119879 = 119879
11198792sdot sdot sdot 119879119898and 119878 = 119878
11198782sdot sdot sdot 119878119899) satisfy the contractive
condition (5) then the component maps of the two families119879119894119898
1and 119878
119894119899
1have a unique common fixed point
Proof FromTheorem 9 we can say that the mappings 119879 and119878 have a unique common fixed point 119911 that is 119879119911 = 119878119911 = 119911Now our requirement is to show that 119911 is a common fixedpoint of all the component mappings of both the families Inviewof pairwise commutativity of the families 119879
119894119898
1and 119878
119894119899
1
(for every 1 le 119896 le 119898) we can write 119879119896119911 = 119879
119896119879119911 = 119879119879
119896119911 and
119879119896119911 = 119879119896119878119911 = 119878119879
119896119911 which show that 119879
119896119911 (for every 119896) is also
a common fixed point of 119879 and 119878 By using the uniqueness ofcommonfixed point we canwrite119879
119896119911 = 119911 (for every 119896) which
shows that 119911 is a common fixed point of the family 119879119894119898
1
Using the same argument one can also show that (for every1 le 119896 le 119899) 119878
119896119911 = 119911Thus componentmaps of the two families
119879119894119898
1and 119878
119894119899
1have a unique common fixed point
By setting 1198791= 1198792= sdot sdot sdot = 119879
119898= 119865 and 119878
1= 1198782= sdot sdot sdot =
119878119899= 119866 in Theorem 18 we get the following corollary
Corollary 19 Let 119865 119866 119883 rarr 119883 be two commuting self-mappings defined on a complete PMS (119883 119901) satisfying thecondition
119901 (119865119898119909 119866119899119910)
le 120572119901 (119909 119910)
+120573119901 (119909 119865
119898119909) 119901 (119910 119866
119899119910) + 120574119901 (119910 119865
119898119909) 119901 (119909 119866
119899119910)
1 + 119901 (119909 119910)
(36)
6 Abstract and Applied Analysis
for all 119909 119910 isin 119883 120572 + 120573 + 2120574 lt 1 (120572 120573 and 120574 are nonnegativereals) Then F and G have a unique common fixed point
By setting 119898 = 119899 and 119865 = 119866 = 119879 in Corollary 19 wededuce the following corollary
Corollary 20 Let 119879 119883 rarr 119883 be a mapping defined on acomplete PMS (119883 119901) satisfying the condition
119901 (119879119899119909 119879119899119910)
le 120572119901 (119909 119910)
+120573119901 (119909 119879
119899119909) 119901 (119910 119879
119899119910) + 120574119901 (119910 119879
119899119909) 119901 (119909 119879
119899119910)
1 + 119901 (119909 119910)
(37)
for all 119909 119910 isin 119883 120572 + 120573 + 2120574 lt 1 (120572 120573 and 120574 are nonnegativereals) Then F has a unique fixed point
By setting 120573 = 120574 = 0 we draw following corollary whichcan be viewed as an extension of Bryantrsquos theorem [15] for amapping on a complete PMS (119883 119901)
Corollary 21 Let 119865 119883 rarr 119883 be a mapping on a completePMS (119883 119901) If 119865 satisfies
119901 (119865119899119909 119865119899119910) le 120572119901 (119909 119910) (38)
for all 119909 119910 isin 119883 120572 lt 1 Then 119865 has a unique fixed point
The following example demonstrates the superiority ofBryantrsquos theorem overMatthews theorem on complete partialmetric space
Example 22 Let119883 = [0 4] Define the partial metric 119901 119883 times
119883 rarr R by
119901 (119909 119910) = max 119909 119910 (39)
Then (119883 119901) is a complete partial metric space Let 119865 119883 rarr
119883 be defined as follows
119865 (119909) =
1199092 if 119909 isin [0 1 [
2 if 119909 isin [1 2 [
0 if 119909 isin [2 4]
(40)
Then for 119909 = 0 and 119910 = 1 we get
119901 (119865 (0) 119865 (1)) = 119901 (0 2) = 2 gt 120572119901 (0 1) = 120572 (1) (41)
because 0 le 120572 lt 1 However 1198652 satisfies the requirement ofBryantrsquos theorem and 119911 = 0 is the unique fixed point of 119865
3 Results for Set Valued Mappings
Theorem23 Let (119883 119901) be a complete partial metric space andlet 119878 119879 119883 rarr 119862119861
119901(119883) be mappings such that
119867119901(119878119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119878119909) 119901 (119910 119879119910) + 120574119901 (119910 119878119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(42)
for all 119909 119910 isin 119883 0 le 120572 120573 120574 with 120572 + 120573 + 2120574 lt 1 Then 119878 and 119879
have a common fixed point
Proof Assume that119872 = ((120572 + 120574)(1 minus 120573 minus 120574)) Let 1199090isin 119883 be
arbitrary but fixed element of 119883 and choose 1199091
isin 119878(1199090) By
Lemma 8 we can choose 1199092isin 119879(119909
1) such that
119901 (1199091 1199092) le 119867
119901(119878 (1199090) 119879 (119909
1)) + (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1198781199090) 119901 (119909
1 1198791199091)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199091 1198781199090) 119901 (119909
0 1198791199091)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1199091) 119901 (119909
1 1199092)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199091 1199091) 119901 (119909
0 1199092)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1199091) 119901 (119909
1 1199092)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199090 1199091) 119901 (119909
0 1199092)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573119901 (119909
1 1199092) + 120574119901 (119909
0 1199092)
+ (120572 + 120574)
(43)
So we get
119901 (1199091 1199092) le (
120572 + 120574
1 minus 120573 minus 120574)119901 (119909
0 1199091) + (
120572 + 120574
1 minus 120573 minus 120574) (44)
Since119872 = ((120572 + 120574)(1 minus 120573 minus 120574)) so it further implies that119901 (1199091 1199092) le 119872119901 (119909
0 1199091) + 119872 (45)
By Lemma 8 we can choose 1199093isin 119878(1199092) such that
119901 (1199092 1199093) le 119867
119901(119879 (1199091) 119878 (119909
2)) +
(120572 + 120574)2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1198791199091) 119901 (119909
2 1198781199092)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199092 1198791199091) 119901 (119909
1 1198781199092)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199092 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199091 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
Abstract and Applied Analysis 7
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199091 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573119901 (119909
2 1199093) + 120574119901 (119909
1 1199093)
+(120572 + 120574)
2
1 minus 120573 minus 120574
(46)
So we get
119901 (1199092 1199093) le (
120572 + 120574
1 minus 120573 minus 120574)
2
119901 (1199090 1199091) + 2(
120572 + 120574
1 minus 120573 minus 120574)
2
(47)
Continuing in this manner one can obtain a sequence 119909119899 in
119883 as 1199092119899+1
isin 119878(1199092119899) and 119909
2119899+2isin 119879(119909
2119899+1) such that
119901 (119909119899 119909119899+1
) le 119872119901 (119909119899minus1
119909119899) + 119872
le sdot sdot sdot le 119872119899119901 (1199090 1199091) + 119899119872
119899
(48)
where 119872 = ((120572 + 120573)(1 minus 120572)) lt 1 for all 119899 ge 0 Without lossof generality assume that 119899 gt 119898 Then using (48) and thetriangle inequality for partial metrics (P
4) we have
119901 (119909119899 119909119898)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119899+2
) + sdot sdot sdot + 119901 (119909119898minus1
119909119898)
le 119872119899119901 (1199090 1199091) + 119899119872
119899+ 119872119899+1
119901 (1199090 1199091)
+ (119899 + 1)119872119899+1
+ sdot sdot sdot + 119872119898minus1
119901 (1199090 1199091)
+ (119898 minus 1)119872119898minus1
le
119898minus1
sum
119894=119899
119872119894119901 (1199090 1199091)
+
119898minus1
sum
119894=119899
119894119872119894997888rarr 0 as 119899 997888rarr +infin (since 0 lt 119872 lt 1)
(49)
By the definition of 119901119904 we get
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (50)
This yields that 119909119899 is a Cauchy sequence in (119883 119901
119904) Since
(119883 119901) is complete then from Lemma 2(4) (119883 119901119904) is a com-
plete metric space Therefore the sequence 119909119899 converges
to some 119909lowast
isin 119883 with respect to the metric 119901119904 that is
lim119899rarr+infin
119901119904(119909119899 119909lowast) = 0 Again from Lemma 2(4) we get
119901 (119909lowast 119909lowast) = lim119899rarr+infin
119901 (119909119899 119909lowast) = lim119899rarr+infin
119901 (119909119899 119909119899) = 0 (51)
119867119901(119879 (1199092119899+2
) 119878 (119909lowast))
le 120572119901 (1199092119899+2
119909lowast)
+ 120573119901 (1199092119899+2
119879 (1199092119899+2
)) 119901 (119909lowast 119878 (119909lowast))
1 + 119901 (1199092119899+2
119909lowast)
+ 120574119901 (1199092119899+2
119878 (119909lowast)) 119901 (119909
lowast 119879 (1199092119899+2
))
1 + 119901 (1199092119899+2
119909lowast)
le 120572119901 (1199092119899+2
119909lowast)
+ 120573119901 (1199092119899+2
1199092119899+3
) 119901 (119909lowast 119878 (119909lowast))
1 + 119901 (1199092119899+2
119909lowast)
+ 120574119901 (1199092119899+2
119878 (119909lowast)) 119901 (119909
lowast 1199092119899+1
)
1 + 119901 (1199092119899+2
119909lowast)
(52)
taking limit as 119899 rarr infin and using (51) we get
lim119899rarr+infin
119867119901(119879 (1199092119899+2
) 119878 (119909lowast)) = 0 (53)
Now 1199092119899+1
isin 119879(1199092119899+2
) gives that
119901 (1199092119899+1
119878 (119909lowast)) le 119867
119901(119879 (1199092119899+2
) 119878 (119909lowast)) (54)
which implies that
lim119899rarr+infin
119901 (1199092119899+1
119878 (119909lowast)) = 0 (55)
On the other hand by (P4) we have
119901 (119909lowast 119878 (119909lowast)) le 119901 (119909
lowast 1199092119899+2
) + 119901 (1199092119899+2
119878 (119909lowast))
minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (119909lowast 1199092119899+2
) + 119901 (1199092119899+2
119878 (119909lowast))
(56)
Taking limit as 119899 rarr +infin and using (51) and (55) we obtain119901(119909lowast 119878(119909lowast)) = 0 Therefore from (51) (119901(119909lowast 119909lowast) = 0) we
obtain
119901 (119909lowast 119878 (119909lowast)) = 119901 (119909
lowast 119909lowast) (57)
which from Remark 14 implies that 119909lowast
isin 119878(119909lowast) = 119878(119909lowast)
Similarly one can easily prove that 119909lowast isin 119879(119909lowast) Thus 119878 and
119879 have a common fixed point
Remark 24 For 120573 = 120574 = 0 and 119878 = 119879 Theorem 23 reduces tothe following result of Aydi et al [9]
Corollary 25 (see [9 Theorem 32]) Let (119883 119901) be a partialmetric space If 119879 119883 rarr 119862119861
119901(119883) is a multivalued mapping
such that for all 119909 119910 isin 119883 one has
119867119901(119879119909 119879119910) le 119896119901 (119886 119887) (58)
where 119896 isin (0 1) Then 119879 has a fixed point
8 Abstract and Applied Analysis
Theorem26 Let (119883 119901) be a complete partialmetric space and119878 119879 119883 rarr 119862119861
119901(119883) be multivalued mappings such that
119867119901(119878119909 119879119910) le 120572
119901 (119909 119878119909) 119901 (119909 119879119910) + 119901 (119910 119879119910) 119901 (119910 119878119909)
119901 (119909 119879119910) + 119901 (119910 119878119909)
+ 120573119889 (119909 119910)
(59)
for all 119909 119910 isin 119883 0 le 120572 120573 with 2120572 + 120573 lt 1 and 119901(119909 119879119910) +
119901(119910 119878119909) = 0 Then 119878 and 119879 have a common fixed point
Proof Assume that 119897 = (120572+120573)(1minus120572) Let 1199090isin 119883 be arbitrary
but fixed element of119883 and choose 1199091isin 119878(1199090)
When 119901(119909 119879119910)+119901(119910 119878119909) = 0 By Lemma 8we can choose1199092isin 119879(119909
1) such that
119901 (1199091 1199092)
le 119867119901(119878 (1199090) 119879 (119909
1)) + (120572 + 120573)
le 120572119901 (1199090 1198781199090) 119901 (119909
0 1198791199091) + 119901 (119909
1 1198791199091) 119901 (119909
1 1198781199090)
119901 (1199090 1198791199091) + 119901 (119909
1 1198781199090)
+ 120573119901 (1199090 1199091) + (120572 + 120573)
le 120572119901 (1199090 1199091) 119901 (119909
0 1199092) + 119901 (119909
1 1199092) 119901 (119909
1 1199091)
119901 (1199090 1199092) + 119901 (119909
1 1199091)
+ 120573119901 (1199090 1199091) + (120572 + 120573)
le 120572 119901 (1199090 1199091) + 119901 (119909
1 1199092) + 120573119901 (119909
0 1199091) + (120572 + 120573)
(60)
because 119901(1199090 1199092) lt 119901(119909
0 1199092) + 119901(119909
1 1199091) and 119901(119909
1 1199091) lt
119901(1199091 1199091) + 119901(119909
0 1199092) Thus we get
119901 (1199091 1199092) le (
120572 + 120573
1 minus 120572)119901 (119909
0 1199091) + (
120572 + 120573
1 minus 120572) (61)
It further implies that
119901 (1199091 1199092) le 119897119901 (119909
0 1199091) + 119897 (62)
By Lemma 8 we can choose 1199093isin 119878(1199092) such that
119901 (1199092 1199093)
le 119867119901(119879 (1199091) 119878 (119909
2)) +
(120572 + 120573)2
1 minus 120572
le 120572119901 (1199091 1198791199091) 119901 (119909
1 1198781199092) + 119901 (119909
2 1198781199092) 119901 (119909
2 1198791199091)
119901 (1199091 1198781199092) + 119901 (119909
2 1198791199091)
+ 120573119901 (1199091 1199092) +
(120572 + 120573)2
1 minus 120572
le 120572119901 (1199091 1199092) 119901 (119909
1 1199093) + 119901 (119909
2 1199093) 119901 (119909
2 1199092)
119901 (1199091 1199093) + 119901 (119909
2 1199092)
+ 120573119901 (1199091 1199092) +
(120572 + 120573)2
1 minus 120572
le 120572 119901 (1199091 1199092) + 119901 (119909
2 1199093) + 120573119901 (119909
1 1199092) +
(120572 + 120573)2
1 minus 120572
(63)
because 119901(1199091 1199093) lt 119901(119909
1 1199093) + 119901(119909
2 1199092) and 119901(119909
2 1199092) lt
119901(1199092 1199092) + 119901(119909
1 1199093) Thus we get
119901 (1199092 1199093) le (
120572 + 120573
1 minus 120572)119901 (119909
1 1199092) + (
120572 + 120573
1 minus 120572)
2
(64)
It further implies that
119901 (1199092 1199093) le 1198972119901 (1199090 1199090) + 21198972 (65)
Continuing in this manner one can obtain a sequence 119909119899 in
119883 as 1199092119899+1
isin 119878(1199092119899) and 119909
2119899+2isin 119879(119909
2119899+1) such that
119901 (119909119899 119909119899+1
) le 119897119901 (119909119899minus1
119909119899) + 119897 le sdot sdot sdot le 119897
119899119901 (1199090 1199091) + 119899119897119899
(66)
where 119897 = ((120572 + 120573)(1 minus 120572)) lt 1 for all 119899 ge 0 Withoutloss of generality assume that 119898 gt 119899 Then using (66) andthe triangle inequality for partial metrics (P
4) one can easily
prove that
119901 (119909119899 119909119898) le
119898minus1
sum
119894=119899
119897119894119901 (1199090 1199091) +
119898minus1
sum
119894=119899
119894119897119894
997888rarr 0 as 119899 997888rarr +infin (since 0 lt 119897 lt 1)
(67)
By the definition of 119901119904
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (68)
This yields that 119909119899 is a Cauchy sequence in (119883 119901
119904) Since
(119883 119901) is complete then from Lemma 2(4) (119883 119901119904) is a com-
plete metric space Therefore the sequence 119909119899 converges
to some 1199091015840
isin 119883 with respect to the metric 119901119904 that is
lim119899rarr+infin
119901119904(119909119899 1199091015840) = 0 Again from Lemma 2(4) we get
119901 (1199091015840 1199091015840) = lim119899rarr+infin
119901 (119909119899 119909) = lim119899rarr+infin
119901 (119909119899 119909119899) = 0
(69)
Abstract and Applied Analysis 9
119867119901(119879 (1199092119899+1
) 119878 (1199091015840))
le 120572 (119901 (1199092119899+1
119879 (1199092119899+1
)) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 119879 (1199092119899+1
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 119879 (1199092119899+1
)))minus1
+ 120573119901 (1199092119899+1
119909)
le 120572 (119901 ((1199092119899+1
1199092119899+2
) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 1199092119899+2
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 1199092119899+2
))minus1
+ 120573119901 (1199092119899+1
119909)
(70)
therefore
lim119899rarr+infin
119867119901(119879 (1199092119899+1
) 119878 (1199091015840)) = 0 (71)
Now 1199092119899+2
isin 119879(1199092119899+1
) gives that
119901 (1199092119899+2
119878 (1199091015840)) le 119867
119901(119879 (1199092119899+1
) 119878 (1199091015840)) (72)
which implies that
lim119899rarr+infin
119901 (1199092119899+2
119878 (1199091015840)) = 0 (73)
On the other hand we have
119901 (1199091015840 119878 (1199091015840)) le 119901 (119909
1015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (1199091015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
(74)
Taking limit as 119899 rarr +infin and using (69) and (73) we obtain119901(1199091015840 119878(1199091015840)) = 0 Therefore from (69) (119901(1199091015840 1199091015840) = 0) we
obtain
119901 (1199091015840 119878 (1199091015840)) = 119901 (119909
1015840 1199091015840) (75)
which from Remark 14 implies that 1199091015840
isin 119878(1199091015840) = 119878(1199091015840)
It follows similarly that 1199091015840
isin 119879(1199091015840) Thus 119878 and 119879 have a
common fixed point
Now we give an example which illustrates our Theo-rem 26
Example 27 Let 119883 = 1 2 3 be endowed with usual orderand let 119901 be a partial metric on119883 defined as
119901 (1 1) = 119901 (2 2) = 0 119901 (3 3) =5
11
119901 (1 2) = 119901 (2 1) =3
10
119901 (1 3) = 119901 (3 1) =9
20
119901 (2 3) = 119901 (3 2) =1
2
(76)
Define the mappings 119878 119879 119883 rarr 119862119861119901(119883) by
119878119909 = 1 if 119909 119910 isin 1 2
1 2 otherwise
119879119909 = 1 if 119909 119910 isin 1 2
2 otherwise
(77)
Note that 119878119909 and 119879119909 are closed and bounded for all 119909 isin 119883
with respect to the partial metric 119901 To show that for all 119909 119910in119883 (59) is satisfied with 120572 = 111 120573 = 45 we consider thefollowing cases if 119909 119910 isin 1 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 1) = 0 (78)
and condition (59) is satisfied obviously
If 119909 = 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 2) =
3
10
119901 (119909 119878119909) = 119901 (119910 119878119909) = 119901 (3 1 2) =9
20
119901 (119909 119879119910) = 119901 (119910 119879119910) = 119901 (119910 119878119909) = 119901 (3 2) =11
24
119901 (119909 119910) = 119901 (3 3) =5
11
(79)
If 119909 = 3 119910 = 1 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (1 1) = 0 119901 (119910 119878119909) = 119901 (1 1 2) = 0
119901 (119909 119910) = 119901 (3 1) =9
20
(80)
10 Abstract and Applied Analysis
If 119909 = 3 119910 = 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (2 1) =3
10 119901 (119910 119878119909) = 119901 (2 1 2) = 0
119901 (119909 119910) = 119901 (3 2) =1
2
(81)
If 119909 = 1 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (1 1) = 0 119901 (119909 119879119910) = 119901 (1 2) =3
10
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (1 3) =9
20
(82)
If 119909 = 2 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (2 1) =3
10 119901 (119909 119879119910) = 119901 (2 2) = 0
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (2 3) =1
2
(83)
Thus all the conditions ofTheorem 26 are satisfied Here 119909 =
1 is a common fixed point of 119878 and 119879On the other hand the metric 119901
119904 induced by the partialmetric 119901 is given by
119901119904(1 1) = 119901
119904(2 2) = 119901
119904(3 3) = 0
119901119904(2 1) = 119901
119904(2 1) =
3
4
119901119904(3 2) = 119901
119904(2 3) =
4
7
119901119904(3 1) = 119901
119904(1 3) =
14
29
(84)
Note that in case of ordinary Hausdorff metric given map-ping does not satisfy the condition Indeed for 119909 = 1 and119910 = 3 we have
119867(119878119909 119879119910) = 119867 (1 2) =3
4
119901119904(119909 119878119909) = 119901
119904(1 1) = 0
119901119904(119909 119879119910) = 119901
119904(1 2) =
3
4
119901119904(119910 119879119910) = 119901
119904(3 2) =
4
7
119901119904(119910 119878119909) = 119901
119904(3 1) =
14
29
(85)
for the values of 120572 = 111 120573 = 45 By a routine calculationone can easily verify that the mapping does not satisfy thecondition which involved ordinary Hausdorff metric
Acknowledgment
This paper was funded by the Deanship of Scientific Research(DSR) King Abdulaziz University Jeddah The authorstherefore acknowledge with thanks DSR technical and finan-cial support
References
[1] S G Matthews ldquoPartial metric topologyrdquo in Proceedings of the8th Summer Conference on General Topology and Applicationsvol 728 pp 183ndash197 New York Academy of Science 1994
[2] T Abdeljawad E Karapinar andK Tas ldquoA generalized contrac-tion principle with control functions on partial metric spacesrdquoComputers amp Mathematics with Applications vol 63 no 3 pp716ndash719 2012
[3] T Abdeljawad ldquoFixed points for generalized weakly contractivemappings in partialmetric spacesrdquoMathematical andComputerModelling vol 54 no 11-12 pp 2923ndash2927 2011
[4] J Ahmad M Arshad and C Vetro ldquoOn a theorem of Khan in ageneralized metric spacerdquo International Journal of Analysis vol2013 Article ID 852727 6 pages 2013
[5] S Alsulami N Hussain and A Alotaibi ldquoCoupled fixed andcoincidence points for monotone operators in partial metricspacesrdquo Fixed Point Theory and Applications vol 2012 article173 2012
[6] I Altun and A Erduran ldquoFixed point theorems for monotonemappings on partial metric spacesrdquo Fixed Point Theory andApplications vol 2011 Article ID 508730 2011
[7] M Arshad J Ahmad and E Karapinar ldquoSome common fixedpoint results in rectangularmetric spacesrdquo International Journalof Analysis vol 2013 Article ID 307234 7 pages 2013
[8] M Arshad E Karapinar and J Ahmad ldquoSome unique fixedpoint theorem for rational contractions in partially orderedmetric spacesrdquo Journal of Inequalities andApplications vol 2013article 248 2013
[9] H Aydi M Abbas and C Vetro ldquoPartial Hausdorff metric andNadlerrsquos fixed point theorem on partial metric spacesrdquo Topologyand Its Applications vol 159 no 14 pp 3234ndash3242 2012
Abstract and Applied Analysis 11
[10] H Aydi M Abbas and C Vetro ldquoCommon Fixed points formultivalued generalized contractions on partial metric spacesrdquoRevista de la Real Academia de Ciencias Exactas Fisicas yNaturales A 2013
[11] A Azam and M Arshad ldquoFixed points of a sequence of locallycontractive multivalued mapsrdquo Computers amp Mathematics withApplications vol 57 no 1 pp 96ndash100 2009
[12] A Azam B Fisher and M Khan ldquoCommon fixed point the-orems in complex valued metric spacesrdquo Numerical FunctionalAnalysis and Optimization vol 32 no 3 pp 243ndash253 2011
[13] S Banach ldquoSur les operations dans les ensembles abstraitset leurs applications aux equations integralesrdquo FundamentaMathematicae vol 3 pp 133ndash181 1922
[14] I Beg and A Azam ldquoFixed points of asymptotically regularmultivalued mappingsrdquo Journal of the Australian MathematicalSociety A vol 53 no 3 pp 313ndash326 1992
[15] V W Bryant ldquoA remark on a fixed-point theorem for iteratedmappingsrdquo The American Mathematical Monthly vol 75 pp399ndash400 1968
[16] K P Chi E Karapınar and T D Thanh ldquoA generalizedcontraction principle in partial metric spacesrdquo Mathematicaland Computer Modelling vol 55 no 5-6 pp 1673ndash1681 2012
[17] N Hussain H K Nashine Z Kadelburg and S M AlsulamildquoWeakly isotone increasingmappings and endpoints in partiallyordered metric spacesrdquo Journal of Inequalities and Applicationsvol 2012 article 232 2012
[18] NHussain DDJoric Z Kadelburg and S Radenovic ldquoSuzuki-type fixed point results in metric type spacesrdquo Fixed PointTheory and Applications vol 2012 article 126 2012
[19] N Hussain Z Kadelburg S Radenovic and F R Al-SolamyldquoComparison functions and fixed point results in partial metricspacesrdquo Abstract and Applied Analysis vol 2012 Article ID605781 15 pages 2012
[20] N Hussain and M Abbas ldquoCommon fixed point results fortwo new classes of hybrid pairs in symmetric spacesrdquo AppliedMathematics and Computation vol 218 no 2 pp 542ndash547 2011
[21] S Hong ldquoFixed points of multivalued operators in orderedmetric spaces with applicationsrdquo Nonlinear Analysis TheoryMethods amp Applications vol 72 no 11 pp 3929ndash3942 2010
[22] S Hong ldquoFixed points for mixed monotone multivalued oper-ators in Banach spaces with applicationsrdquo Journal of Mathemat-ical Analysis and Applications vol 337 no 1 pp 333ndash342 2008
[23] S Hong ldquoFixed points of discontinuous multivalued increasingoperators in Banach spaces with applicationsrdquo Journal of Math-ematical Analysis and Applications vol 282 no 1 pp 151ndash1622003
[24] M Imdad J Ali and M Tanveer ldquoCoincidence and commonfixed point theorems for nonlinear contractions in Menger PMspacesrdquo Chaos Solitons amp Fractals vol 42 no 5 pp 3121ndash31292009
[25] E Karapinar ldquoCiric type nonunique fixed point theorems onpartial metric spacesrdquo The Journal of Nonlinear Science andApplications vol 5 no 2 pp 74ndash83 2012
[26] E Karapnar and I M Erhan ldquoFixed point theorems for opera-tors on partial metric spacesrdquo Applied Mathematics Letters vol24 no 11 pp 1894ndash1899 2011
[27] E KarapinarMMarudai andV Pragadeeshwarar ldquoFixed pointtheorems for generalized weak contractions satisfying rationalexpressions on ordered Partial Metric Spacerdquo LobachevskiiJournal of Mathematics vol 34 no 1 pp 116ndash123 2013
[28] M S Khan M Swaleh and M Imdad Some Fixed PointTheorems IV Communications 1983
Submit your manuscripts athttpwwwhindawicom
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Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Algebra
Discrete Dynamics in Nature and Society
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Decision SciencesAdvances in
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Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
4 Abstract and Applied Analysis
119906lowastisin 119861(119909
0 119903) be another common fixed point of 119878 and119879 that
is 119906lowast = 119878119906lowast= 119879119906lowast Then
119901 (119906 119906lowast) = 119901 (119878119906 119879119906
lowast)
le 120572119901 (119906 119906lowast)
+120573119901 (119906 119878119906) 119901 (119906
lowast 119879119906lowast)+120574119901 (119906
lowast 119878119906) 119901 (119906 119879119906
lowast)
1+119901 (119906 119906lowast)
= 120572119901 (119906 119906lowast) +
120574119901 (119906lowast 119906) 119901 (119906 119906
lowast)
1 + 119901 (119906 119906lowast)
(22)
so that119901(119906 119906lowast) le 120572119901(119906 119906lowast)+120574119901(119906 119906
lowast) because 1+119901(119906 119906
lowast) gt
119901(119906 119906lowast) Therefore 119901(119906 119906
lowast) le (120572 + 120574)119901(119906 119906
lowast) which is a
contradiction so that 119906 = 119906lowast (as 120572 + 120574 lt 1) Hence 119878 and
119879 have a unique common fixed point in 119861(1199090 119903)
Example 10 Let119883 = [0 +infin) endowed with the usual partialmetric 119901 defined by 119901 119883 times 119883 rarr R+ with 119901(119909 119910) =
max119909 119910 Clearly (119883 119901) is a partial metric space Now wedefine 119878 119879 119883 rarr 119883 as
119878 (119909) =
119909
16if 0 le 119909 le 1
119909 minus1
6if 119909 gt 1
119879 (119909) =
5119909
17if 0 le 119909 le 1
119909 minus1
7if 119909 gt 1
(23)
for all 119909 isin 119883 Taking 120572 = 15 120573 = 16 120574 = 18 1199090= 12
and 119903 = 12 then 119861119901(1199090 119903) = [0 1] Also we have 119901(119909
0 1199090) =
max12 12 = 12 120582 = (120572 + 120574)(1 minus 120573 minus 120574) = 3985 with
(1 minus 120582) (119903 + 119901 (1199090 1199090)) =
46
85
119901 (1199090 1198781199090) = 119901 (
1
21
32) =
1
2lt (1 minus 120582) (119903 + 119901 (119909
0 1199090))
(24)
Also if 119909 119910 isin (1 +infin) then
119901 (119878119909 119879119910) = max 119909 minus1
6 119909 minus
1
7 ge
1
5max 119909 119910
+ (1
6max 119909 119909 minus
1
6max 119910 119910 minus
1
7
+1
8max 119910 119909 minus
1
6max 119909 119910 minus
1
7)
times (1 +max 119909 119910)minus1
= 120572119901 (119909 119910)
+120573119901 (119909 119878119909) 119901 (119910 119879119910) + 120574119901 (119910 119878119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(25)
So the contractive condition does not hold on whole of 119883Now if 119909 119910 isin 119861
119901(1199090 119903) then
119901 (119878119909 119879119910) = max 119909
165119910
17 le
1
5max 119909 119910
+ (1
6max 119909 119909 minus
1
6max 119910 119910 minus
1
7
+1
8max 119910 119909 minus
1
6max 119909 119910 minus
1
7)
times (1 +max 119909 119910)minus1
(26)
Therefore all the conditions of Theorem 9 are satisfied Thus0 is the common fixed point of 119878 and 119879 and 119901(0 0) = 0Moreover note that for any metric 119889 on119883
119889 (1198781 1198791) = 119889 (1
165
17) gt
1
5119889 (1 1)
+ (1
6119889 (1
1
16) 119889 (1
5
17)
+1
8119889 (1
1
16) 119889 (1
5
17))
times (1 + 119889 (1 1))minus1
(27)
Therefore commonfixed points of 119878 and119879 cannot be obtainedfrom a metric fixed point theorem
Corollary 11 Let 119878 119879 119883 rarr 119883 be mappings on a completePMS (119883 119901) Suppose that there exist nonnegative reals 120572 120573and 120574 such that 120572 + 120573 + 2120574 lt 1 If 119878 and 119879 satisfy
119901 (119878119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119878119909) 119901 (119910 119879119910) + 120574119901 (119910 119878119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(28)
for all 119909 119910 isin 119883 Then there exists a unique point 119906 isin 119883 suchthat 119906 = 119878119906 = 119879119906 Also 119901(119906 119906) = 0 Further 119878 and 119879 have nofixed point other than 119906
By choosing 120573 = 120574 = 0 in Corollary 11 we get thefollowing corollary
Corollary 12 Let 119878 119879 119883 rarr 119883 be a mappings on completePMS (119883 119901) If 119878 and 119879 satisfy
119901 (119878119909 119879119910) le 120572119901 (119909 119910) (29)
for all 119909 119910 isin 119883 120572 lt 1 (120572 is a nonnegative real) Then 119878 and 119879
have a common fixed point 119906 isin 119883 and 119901(119906 119906) = 0
Remark 13 If we impose Banach type contractive conditionfor a pair 119878 119879 119883 rarr 119883 of mappings on a metric space(119883 119889) that is 119889(119878119909 119879119910) le 120572119889(119909 119910) for all 119909 119910 isin 119883 andthen it follows that 119878119909 = 119879119909 for all 119909 isin 119883 (ie 119878 and 119879 are
Abstract and Applied Analysis 5
equal) Therefore the above condition fails to find commonfixed points of 119878 and 119879 This can be seen as
119889 (1198781 1198791) = 119889 ((1
16) (
5
17)) gt 120572119889 (1 1) = 0 (30)
However the same condition in partial metric space does notassert that 119878 = 119879 This can be seen as by taking the partialmetric same as in Example 10
119901 (1198781 1198791) = 119901 ((1
16) (
5
17)) =
5
17le 120572119901 (1 1) = 120572 (1)
(31)
for any 120572 ge 13 Hence Corollary 12 cannot be obtained froma metric fixed point theorem
Remark 14 By equating 120572 120573 120574 to 0 in all possible combi-nations one can derive a host of corollaries which includeMatthews theorem for mappings defined on a completepartial metric space
By taking 119878 = 119879 in the Theorem 9 we get the followingcorollary
Corollary 15 Let 119879 119883 rarr 119883 be a mapping on a completePMS (119883 119901) and 119909
0 119909 119910 isin 119883 and 119903 gt 0 Suppose that there
exist nonnegative reals 120572 120573 and 120574 such that 120572 + 120573 + 2120574 lt 1 If119879 satisfies
119901 (119879119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119879119909) 119901 (119910 119879119910) + 120574119901 (119910 119879119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(32)
for all 119909 119910 isin 119861119901(1199090 119903)
119901 (1199090 1198791199090) le (1 minus 120582) (119903 + 119901 (119909
0 1199090)) (33)
where 120582 = (120572+ 120574)(1 minus120573minus 120574) Then there exists a unique point119906 isin 119861
119901(1199090 119903) such that 119906 = 119879119906 Also 119901(119906 119906) = 0 Further 119879
has no fixed point other than 119906
By taking 119878 = 119879 in Corollary 11 we get the followingcorollary
Corollary 16 Let 119879 119883 rarr 119883 be a mapping on a completePMS (119883 119901) Suppose that there exist nonnegative reals 120572 120573and 120574 such that 120572 + 120573 + 2120574 lt 1 If 119879 satisfies
119901 (119879119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119879119909) 119901 (119910 119879119910) + 120574119901 (119910 119879119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(34)
for all 119909 119910 isin 119883 Then there exists a unique point 119906 isin 119883 suchthat 119906 = 119879119906 Also 119901(119906 119906) = 0 Further 119879 has no fixed pointother than 119906
Now we give an example in favour of Corollary 16
Example 17 Let 119883 = [0 4] endowed with the usual partialmetric 119901 defined by 119901(119909 119910) = max119909 119910 Clearly (119883 119901) is acomplete partial metric space Now we define 119865 119883 rarr 119883 asfollows
119865 (119909) =
119909
3if 0 le 119909 lt 2
119909
1 + 119909if 2 le 119909 le 4
(35)
for all 119909 isin 119883 Now let 119910 le 119909 If 119909 isin [0 2) (and so 119910 isin [0 2))Then 119901(119865119909 119865119910) = 1199093 119901(119909 119910) = 119909 119901(119909 119865119909) = 119909 119901(119910 119865119910) =
119910 119901(119910 119865119909) = 1199093 119901(119909 119865119910) = 119909 Taking 120572 = 13 120573 = 115120574 = 215 we can prove that all the conditions of Corollary 16are satisfied Now if 119909 isin [2 4] then 119901(119865119909 119865119910) = 119909(1 + 119909)119901(119909 119910) = 119909 119901(119909 119865119909) = 119909 119901(119910 119865119910) = 119910 119901(119910 119865119909) = 119909(1+119909)119901(119909 119865119910) = 119909 and taking 120572 = 13 120573 = 115 120574 = 215 onecan verify the condition of the above corollary Thus all theconditions of Corollary 16 are satisfied and 119906 = 0 is a fixedpoint of the mapping 119865
As an application of Theorem 9 we prove the followingtheorem for two finite families of mappings
Theorem 18 If 119879119894119898
1and 119878
119894119899
1are two pairwise commuting
finite families of self-mapping defined on a complete partialmetric space (119883 119901) such that the mappings 119878 and 119879 (with119879 = 119879
11198792sdot sdot sdot 119879119898and 119878 = 119878
11198782sdot sdot sdot 119878119899) satisfy the contractive
condition (5) then the component maps of the two families119879119894119898
1and 119878
119894119899
1have a unique common fixed point
Proof FromTheorem 9 we can say that the mappings 119879 and119878 have a unique common fixed point 119911 that is 119879119911 = 119878119911 = 119911Now our requirement is to show that 119911 is a common fixedpoint of all the component mappings of both the families Inviewof pairwise commutativity of the families 119879
119894119898
1and 119878
119894119899
1
(for every 1 le 119896 le 119898) we can write 119879119896119911 = 119879
119896119879119911 = 119879119879
119896119911 and
119879119896119911 = 119879119896119878119911 = 119878119879
119896119911 which show that 119879
119896119911 (for every 119896) is also
a common fixed point of 119879 and 119878 By using the uniqueness ofcommonfixed point we canwrite119879
119896119911 = 119911 (for every 119896) which
shows that 119911 is a common fixed point of the family 119879119894119898
1
Using the same argument one can also show that (for every1 le 119896 le 119899) 119878
119896119911 = 119911Thus componentmaps of the two families
119879119894119898
1and 119878
119894119899
1have a unique common fixed point
By setting 1198791= 1198792= sdot sdot sdot = 119879
119898= 119865 and 119878
1= 1198782= sdot sdot sdot =
119878119899= 119866 in Theorem 18 we get the following corollary
Corollary 19 Let 119865 119866 119883 rarr 119883 be two commuting self-mappings defined on a complete PMS (119883 119901) satisfying thecondition
119901 (119865119898119909 119866119899119910)
le 120572119901 (119909 119910)
+120573119901 (119909 119865
119898119909) 119901 (119910 119866
119899119910) + 120574119901 (119910 119865
119898119909) 119901 (119909 119866
119899119910)
1 + 119901 (119909 119910)
(36)
6 Abstract and Applied Analysis
for all 119909 119910 isin 119883 120572 + 120573 + 2120574 lt 1 (120572 120573 and 120574 are nonnegativereals) Then F and G have a unique common fixed point
By setting 119898 = 119899 and 119865 = 119866 = 119879 in Corollary 19 wededuce the following corollary
Corollary 20 Let 119879 119883 rarr 119883 be a mapping defined on acomplete PMS (119883 119901) satisfying the condition
119901 (119879119899119909 119879119899119910)
le 120572119901 (119909 119910)
+120573119901 (119909 119879
119899119909) 119901 (119910 119879
119899119910) + 120574119901 (119910 119879
119899119909) 119901 (119909 119879
119899119910)
1 + 119901 (119909 119910)
(37)
for all 119909 119910 isin 119883 120572 + 120573 + 2120574 lt 1 (120572 120573 and 120574 are nonnegativereals) Then F has a unique fixed point
By setting 120573 = 120574 = 0 we draw following corollary whichcan be viewed as an extension of Bryantrsquos theorem [15] for amapping on a complete PMS (119883 119901)
Corollary 21 Let 119865 119883 rarr 119883 be a mapping on a completePMS (119883 119901) If 119865 satisfies
119901 (119865119899119909 119865119899119910) le 120572119901 (119909 119910) (38)
for all 119909 119910 isin 119883 120572 lt 1 Then 119865 has a unique fixed point
The following example demonstrates the superiority ofBryantrsquos theorem overMatthews theorem on complete partialmetric space
Example 22 Let119883 = [0 4] Define the partial metric 119901 119883 times
119883 rarr R by
119901 (119909 119910) = max 119909 119910 (39)
Then (119883 119901) is a complete partial metric space Let 119865 119883 rarr
119883 be defined as follows
119865 (119909) =
1199092 if 119909 isin [0 1 [
2 if 119909 isin [1 2 [
0 if 119909 isin [2 4]
(40)
Then for 119909 = 0 and 119910 = 1 we get
119901 (119865 (0) 119865 (1)) = 119901 (0 2) = 2 gt 120572119901 (0 1) = 120572 (1) (41)
because 0 le 120572 lt 1 However 1198652 satisfies the requirement ofBryantrsquos theorem and 119911 = 0 is the unique fixed point of 119865
3 Results for Set Valued Mappings
Theorem23 Let (119883 119901) be a complete partial metric space andlet 119878 119879 119883 rarr 119862119861
119901(119883) be mappings such that
119867119901(119878119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119878119909) 119901 (119910 119879119910) + 120574119901 (119910 119878119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(42)
for all 119909 119910 isin 119883 0 le 120572 120573 120574 with 120572 + 120573 + 2120574 lt 1 Then 119878 and 119879
have a common fixed point
Proof Assume that119872 = ((120572 + 120574)(1 minus 120573 minus 120574)) Let 1199090isin 119883 be
arbitrary but fixed element of 119883 and choose 1199091
isin 119878(1199090) By
Lemma 8 we can choose 1199092isin 119879(119909
1) such that
119901 (1199091 1199092) le 119867
119901(119878 (1199090) 119879 (119909
1)) + (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1198781199090) 119901 (119909
1 1198791199091)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199091 1198781199090) 119901 (119909
0 1198791199091)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1199091) 119901 (119909
1 1199092)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199091 1199091) 119901 (119909
0 1199092)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1199091) 119901 (119909
1 1199092)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199090 1199091) 119901 (119909
0 1199092)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573119901 (119909
1 1199092) + 120574119901 (119909
0 1199092)
+ (120572 + 120574)
(43)
So we get
119901 (1199091 1199092) le (
120572 + 120574
1 minus 120573 minus 120574)119901 (119909
0 1199091) + (
120572 + 120574
1 minus 120573 minus 120574) (44)
Since119872 = ((120572 + 120574)(1 minus 120573 minus 120574)) so it further implies that119901 (1199091 1199092) le 119872119901 (119909
0 1199091) + 119872 (45)
By Lemma 8 we can choose 1199093isin 119878(1199092) such that
119901 (1199092 1199093) le 119867
119901(119879 (1199091) 119878 (119909
2)) +
(120572 + 120574)2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1198791199091) 119901 (119909
2 1198781199092)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199092 1198791199091) 119901 (119909
1 1198781199092)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199092 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199091 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
Abstract and Applied Analysis 7
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199091 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573119901 (119909
2 1199093) + 120574119901 (119909
1 1199093)
+(120572 + 120574)
2
1 minus 120573 minus 120574
(46)
So we get
119901 (1199092 1199093) le (
120572 + 120574
1 minus 120573 minus 120574)
2
119901 (1199090 1199091) + 2(
120572 + 120574
1 minus 120573 minus 120574)
2
(47)
Continuing in this manner one can obtain a sequence 119909119899 in
119883 as 1199092119899+1
isin 119878(1199092119899) and 119909
2119899+2isin 119879(119909
2119899+1) such that
119901 (119909119899 119909119899+1
) le 119872119901 (119909119899minus1
119909119899) + 119872
le sdot sdot sdot le 119872119899119901 (1199090 1199091) + 119899119872
119899
(48)
where 119872 = ((120572 + 120573)(1 minus 120572)) lt 1 for all 119899 ge 0 Without lossof generality assume that 119899 gt 119898 Then using (48) and thetriangle inequality for partial metrics (P
4) we have
119901 (119909119899 119909119898)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119899+2
) + sdot sdot sdot + 119901 (119909119898minus1
119909119898)
le 119872119899119901 (1199090 1199091) + 119899119872
119899+ 119872119899+1
119901 (1199090 1199091)
+ (119899 + 1)119872119899+1
+ sdot sdot sdot + 119872119898minus1
119901 (1199090 1199091)
+ (119898 minus 1)119872119898minus1
le
119898minus1
sum
119894=119899
119872119894119901 (1199090 1199091)
+
119898minus1
sum
119894=119899
119894119872119894997888rarr 0 as 119899 997888rarr +infin (since 0 lt 119872 lt 1)
(49)
By the definition of 119901119904 we get
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (50)
This yields that 119909119899 is a Cauchy sequence in (119883 119901
119904) Since
(119883 119901) is complete then from Lemma 2(4) (119883 119901119904) is a com-
plete metric space Therefore the sequence 119909119899 converges
to some 119909lowast
isin 119883 with respect to the metric 119901119904 that is
lim119899rarr+infin
119901119904(119909119899 119909lowast) = 0 Again from Lemma 2(4) we get
119901 (119909lowast 119909lowast) = lim119899rarr+infin
119901 (119909119899 119909lowast) = lim119899rarr+infin
119901 (119909119899 119909119899) = 0 (51)
119867119901(119879 (1199092119899+2
) 119878 (119909lowast))
le 120572119901 (1199092119899+2
119909lowast)
+ 120573119901 (1199092119899+2
119879 (1199092119899+2
)) 119901 (119909lowast 119878 (119909lowast))
1 + 119901 (1199092119899+2
119909lowast)
+ 120574119901 (1199092119899+2
119878 (119909lowast)) 119901 (119909
lowast 119879 (1199092119899+2
))
1 + 119901 (1199092119899+2
119909lowast)
le 120572119901 (1199092119899+2
119909lowast)
+ 120573119901 (1199092119899+2
1199092119899+3
) 119901 (119909lowast 119878 (119909lowast))
1 + 119901 (1199092119899+2
119909lowast)
+ 120574119901 (1199092119899+2
119878 (119909lowast)) 119901 (119909
lowast 1199092119899+1
)
1 + 119901 (1199092119899+2
119909lowast)
(52)
taking limit as 119899 rarr infin and using (51) we get
lim119899rarr+infin
119867119901(119879 (1199092119899+2
) 119878 (119909lowast)) = 0 (53)
Now 1199092119899+1
isin 119879(1199092119899+2
) gives that
119901 (1199092119899+1
119878 (119909lowast)) le 119867
119901(119879 (1199092119899+2
) 119878 (119909lowast)) (54)
which implies that
lim119899rarr+infin
119901 (1199092119899+1
119878 (119909lowast)) = 0 (55)
On the other hand by (P4) we have
119901 (119909lowast 119878 (119909lowast)) le 119901 (119909
lowast 1199092119899+2
) + 119901 (1199092119899+2
119878 (119909lowast))
minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (119909lowast 1199092119899+2
) + 119901 (1199092119899+2
119878 (119909lowast))
(56)
Taking limit as 119899 rarr +infin and using (51) and (55) we obtain119901(119909lowast 119878(119909lowast)) = 0 Therefore from (51) (119901(119909lowast 119909lowast) = 0) we
obtain
119901 (119909lowast 119878 (119909lowast)) = 119901 (119909
lowast 119909lowast) (57)
which from Remark 14 implies that 119909lowast
isin 119878(119909lowast) = 119878(119909lowast)
Similarly one can easily prove that 119909lowast isin 119879(119909lowast) Thus 119878 and
119879 have a common fixed point
Remark 24 For 120573 = 120574 = 0 and 119878 = 119879 Theorem 23 reduces tothe following result of Aydi et al [9]
Corollary 25 (see [9 Theorem 32]) Let (119883 119901) be a partialmetric space If 119879 119883 rarr 119862119861
119901(119883) is a multivalued mapping
such that for all 119909 119910 isin 119883 one has
119867119901(119879119909 119879119910) le 119896119901 (119886 119887) (58)
where 119896 isin (0 1) Then 119879 has a fixed point
8 Abstract and Applied Analysis
Theorem26 Let (119883 119901) be a complete partialmetric space and119878 119879 119883 rarr 119862119861
119901(119883) be multivalued mappings such that
119867119901(119878119909 119879119910) le 120572
119901 (119909 119878119909) 119901 (119909 119879119910) + 119901 (119910 119879119910) 119901 (119910 119878119909)
119901 (119909 119879119910) + 119901 (119910 119878119909)
+ 120573119889 (119909 119910)
(59)
for all 119909 119910 isin 119883 0 le 120572 120573 with 2120572 + 120573 lt 1 and 119901(119909 119879119910) +
119901(119910 119878119909) = 0 Then 119878 and 119879 have a common fixed point
Proof Assume that 119897 = (120572+120573)(1minus120572) Let 1199090isin 119883 be arbitrary
but fixed element of119883 and choose 1199091isin 119878(1199090)
When 119901(119909 119879119910)+119901(119910 119878119909) = 0 By Lemma 8we can choose1199092isin 119879(119909
1) such that
119901 (1199091 1199092)
le 119867119901(119878 (1199090) 119879 (119909
1)) + (120572 + 120573)
le 120572119901 (1199090 1198781199090) 119901 (119909
0 1198791199091) + 119901 (119909
1 1198791199091) 119901 (119909
1 1198781199090)
119901 (1199090 1198791199091) + 119901 (119909
1 1198781199090)
+ 120573119901 (1199090 1199091) + (120572 + 120573)
le 120572119901 (1199090 1199091) 119901 (119909
0 1199092) + 119901 (119909
1 1199092) 119901 (119909
1 1199091)
119901 (1199090 1199092) + 119901 (119909
1 1199091)
+ 120573119901 (1199090 1199091) + (120572 + 120573)
le 120572 119901 (1199090 1199091) + 119901 (119909
1 1199092) + 120573119901 (119909
0 1199091) + (120572 + 120573)
(60)
because 119901(1199090 1199092) lt 119901(119909
0 1199092) + 119901(119909
1 1199091) and 119901(119909
1 1199091) lt
119901(1199091 1199091) + 119901(119909
0 1199092) Thus we get
119901 (1199091 1199092) le (
120572 + 120573
1 minus 120572)119901 (119909
0 1199091) + (
120572 + 120573
1 minus 120572) (61)
It further implies that
119901 (1199091 1199092) le 119897119901 (119909
0 1199091) + 119897 (62)
By Lemma 8 we can choose 1199093isin 119878(1199092) such that
119901 (1199092 1199093)
le 119867119901(119879 (1199091) 119878 (119909
2)) +
(120572 + 120573)2
1 minus 120572
le 120572119901 (1199091 1198791199091) 119901 (119909
1 1198781199092) + 119901 (119909
2 1198781199092) 119901 (119909
2 1198791199091)
119901 (1199091 1198781199092) + 119901 (119909
2 1198791199091)
+ 120573119901 (1199091 1199092) +
(120572 + 120573)2
1 minus 120572
le 120572119901 (1199091 1199092) 119901 (119909
1 1199093) + 119901 (119909
2 1199093) 119901 (119909
2 1199092)
119901 (1199091 1199093) + 119901 (119909
2 1199092)
+ 120573119901 (1199091 1199092) +
(120572 + 120573)2
1 minus 120572
le 120572 119901 (1199091 1199092) + 119901 (119909
2 1199093) + 120573119901 (119909
1 1199092) +
(120572 + 120573)2
1 minus 120572
(63)
because 119901(1199091 1199093) lt 119901(119909
1 1199093) + 119901(119909
2 1199092) and 119901(119909
2 1199092) lt
119901(1199092 1199092) + 119901(119909
1 1199093) Thus we get
119901 (1199092 1199093) le (
120572 + 120573
1 minus 120572)119901 (119909
1 1199092) + (
120572 + 120573
1 minus 120572)
2
(64)
It further implies that
119901 (1199092 1199093) le 1198972119901 (1199090 1199090) + 21198972 (65)
Continuing in this manner one can obtain a sequence 119909119899 in
119883 as 1199092119899+1
isin 119878(1199092119899) and 119909
2119899+2isin 119879(119909
2119899+1) such that
119901 (119909119899 119909119899+1
) le 119897119901 (119909119899minus1
119909119899) + 119897 le sdot sdot sdot le 119897
119899119901 (1199090 1199091) + 119899119897119899
(66)
where 119897 = ((120572 + 120573)(1 minus 120572)) lt 1 for all 119899 ge 0 Withoutloss of generality assume that 119898 gt 119899 Then using (66) andthe triangle inequality for partial metrics (P
4) one can easily
prove that
119901 (119909119899 119909119898) le
119898minus1
sum
119894=119899
119897119894119901 (1199090 1199091) +
119898minus1
sum
119894=119899
119894119897119894
997888rarr 0 as 119899 997888rarr +infin (since 0 lt 119897 lt 1)
(67)
By the definition of 119901119904
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (68)
This yields that 119909119899 is a Cauchy sequence in (119883 119901
119904) Since
(119883 119901) is complete then from Lemma 2(4) (119883 119901119904) is a com-
plete metric space Therefore the sequence 119909119899 converges
to some 1199091015840
isin 119883 with respect to the metric 119901119904 that is
lim119899rarr+infin
119901119904(119909119899 1199091015840) = 0 Again from Lemma 2(4) we get
119901 (1199091015840 1199091015840) = lim119899rarr+infin
119901 (119909119899 119909) = lim119899rarr+infin
119901 (119909119899 119909119899) = 0
(69)
Abstract and Applied Analysis 9
119867119901(119879 (1199092119899+1
) 119878 (1199091015840))
le 120572 (119901 (1199092119899+1
119879 (1199092119899+1
)) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 119879 (1199092119899+1
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 119879 (1199092119899+1
)))minus1
+ 120573119901 (1199092119899+1
119909)
le 120572 (119901 ((1199092119899+1
1199092119899+2
) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 1199092119899+2
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 1199092119899+2
))minus1
+ 120573119901 (1199092119899+1
119909)
(70)
therefore
lim119899rarr+infin
119867119901(119879 (1199092119899+1
) 119878 (1199091015840)) = 0 (71)
Now 1199092119899+2
isin 119879(1199092119899+1
) gives that
119901 (1199092119899+2
119878 (1199091015840)) le 119867
119901(119879 (1199092119899+1
) 119878 (1199091015840)) (72)
which implies that
lim119899rarr+infin
119901 (1199092119899+2
119878 (1199091015840)) = 0 (73)
On the other hand we have
119901 (1199091015840 119878 (1199091015840)) le 119901 (119909
1015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (1199091015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
(74)
Taking limit as 119899 rarr +infin and using (69) and (73) we obtain119901(1199091015840 119878(1199091015840)) = 0 Therefore from (69) (119901(1199091015840 1199091015840) = 0) we
obtain
119901 (1199091015840 119878 (1199091015840)) = 119901 (119909
1015840 1199091015840) (75)
which from Remark 14 implies that 1199091015840
isin 119878(1199091015840) = 119878(1199091015840)
It follows similarly that 1199091015840
isin 119879(1199091015840) Thus 119878 and 119879 have a
common fixed point
Now we give an example which illustrates our Theo-rem 26
Example 27 Let 119883 = 1 2 3 be endowed with usual orderand let 119901 be a partial metric on119883 defined as
119901 (1 1) = 119901 (2 2) = 0 119901 (3 3) =5
11
119901 (1 2) = 119901 (2 1) =3
10
119901 (1 3) = 119901 (3 1) =9
20
119901 (2 3) = 119901 (3 2) =1
2
(76)
Define the mappings 119878 119879 119883 rarr 119862119861119901(119883) by
119878119909 = 1 if 119909 119910 isin 1 2
1 2 otherwise
119879119909 = 1 if 119909 119910 isin 1 2
2 otherwise
(77)
Note that 119878119909 and 119879119909 are closed and bounded for all 119909 isin 119883
with respect to the partial metric 119901 To show that for all 119909 119910in119883 (59) is satisfied with 120572 = 111 120573 = 45 we consider thefollowing cases if 119909 119910 isin 1 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 1) = 0 (78)
and condition (59) is satisfied obviously
If 119909 = 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 2) =
3
10
119901 (119909 119878119909) = 119901 (119910 119878119909) = 119901 (3 1 2) =9
20
119901 (119909 119879119910) = 119901 (119910 119879119910) = 119901 (119910 119878119909) = 119901 (3 2) =11
24
119901 (119909 119910) = 119901 (3 3) =5
11
(79)
If 119909 = 3 119910 = 1 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (1 1) = 0 119901 (119910 119878119909) = 119901 (1 1 2) = 0
119901 (119909 119910) = 119901 (3 1) =9
20
(80)
10 Abstract and Applied Analysis
If 119909 = 3 119910 = 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (2 1) =3
10 119901 (119910 119878119909) = 119901 (2 1 2) = 0
119901 (119909 119910) = 119901 (3 2) =1
2
(81)
If 119909 = 1 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (1 1) = 0 119901 (119909 119879119910) = 119901 (1 2) =3
10
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (1 3) =9
20
(82)
If 119909 = 2 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (2 1) =3
10 119901 (119909 119879119910) = 119901 (2 2) = 0
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (2 3) =1
2
(83)
Thus all the conditions ofTheorem 26 are satisfied Here 119909 =
1 is a common fixed point of 119878 and 119879On the other hand the metric 119901
119904 induced by the partialmetric 119901 is given by
119901119904(1 1) = 119901
119904(2 2) = 119901
119904(3 3) = 0
119901119904(2 1) = 119901
119904(2 1) =
3
4
119901119904(3 2) = 119901
119904(2 3) =
4
7
119901119904(3 1) = 119901
119904(1 3) =
14
29
(84)
Note that in case of ordinary Hausdorff metric given map-ping does not satisfy the condition Indeed for 119909 = 1 and119910 = 3 we have
119867(119878119909 119879119910) = 119867 (1 2) =3
4
119901119904(119909 119878119909) = 119901
119904(1 1) = 0
119901119904(119909 119879119910) = 119901
119904(1 2) =
3
4
119901119904(119910 119879119910) = 119901
119904(3 2) =
4
7
119901119904(119910 119878119909) = 119901
119904(3 1) =
14
29
(85)
for the values of 120572 = 111 120573 = 45 By a routine calculationone can easily verify that the mapping does not satisfy thecondition which involved ordinary Hausdorff metric
Acknowledgment
This paper was funded by the Deanship of Scientific Research(DSR) King Abdulaziz University Jeddah The authorstherefore acknowledge with thanks DSR technical and finan-cial support
References
[1] S G Matthews ldquoPartial metric topologyrdquo in Proceedings of the8th Summer Conference on General Topology and Applicationsvol 728 pp 183ndash197 New York Academy of Science 1994
[2] T Abdeljawad E Karapinar andK Tas ldquoA generalized contrac-tion principle with control functions on partial metric spacesrdquoComputers amp Mathematics with Applications vol 63 no 3 pp716ndash719 2012
[3] T Abdeljawad ldquoFixed points for generalized weakly contractivemappings in partialmetric spacesrdquoMathematical andComputerModelling vol 54 no 11-12 pp 2923ndash2927 2011
[4] J Ahmad M Arshad and C Vetro ldquoOn a theorem of Khan in ageneralized metric spacerdquo International Journal of Analysis vol2013 Article ID 852727 6 pages 2013
[5] S Alsulami N Hussain and A Alotaibi ldquoCoupled fixed andcoincidence points for monotone operators in partial metricspacesrdquo Fixed Point Theory and Applications vol 2012 article173 2012
[6] I Altun and A Erduran ldquoFixed point theorems for monotonemappings on partial metric spacesrdquo Fixed Point Theory andApplications vol 2011 Article ID 508730 2011
[7] M Arshad J Ahmad and E Karapinar ldquoSome common fixedpoint results in rectangularmetric spacesrdquo International Journalof Analysis vol 2013 Article ID 307234 7 pages 2013
[8] M Arshad E Karapinar and J Ahmad ldquoSome unique fixedpoint theorem for rational contractions in partially orderedmetric spacesrdquo Journal of Inequalities andApplications vol 2013article 248 2013
[9] H Aydi M Abbas and C Vetro ldquoPartial Hausdorff metric andNadlerrsquos fixed point theorem on partial metric spacesrdquo Topologyand Its Applications vol 159 no 14 pp 3234ndash3242 2012
Abstract and Applied Analysis 11
[10] H Aydi M Abbas and C Vetro ldquoCommon Fixed points formultivalued generalized contractions on partial metric spacesrdquoRevista de la Real Academia de Ciencias Exactas Fisicas yNaturales A 2013
[11] A Azam and M Arshad ldquoFixed points of a sequence of locallycontractive multivalued mapsrdquo Computers amp Mathematics withApplications vol 57 no 1 pp 96ndash100 2009
[12] A Azam B Fisher and M Khan ldquoCommon fixed point the-orems in complex valued metric spacesrdquo Numerical FunctionalAnalysis and Optimization vol 32 no 3 pp 243ndash253 2011
[13] S Banach ldquoSur les operations dans les ensembles abstraitset leurs applications aux equations integralesrdquo FundamentaMathematicae vol 3 pp 133ndash181 1922
[14] I Beg and A Azam ldquoFixed points of asymptotically regularmultivalued mappingsrdquo Journal of the Australian MathematicalSociety A vol 53 no 3 pp 313ndash326 1992
[15] V W Bryant ldquoA remark on a fixed-point theorem for iteratedmappingsrdquo The American Mathematical Monthly vol 75 pp399ndash400 1968
[16] K P Chi E Karapınar and T D Thanh ldquoA generalizedcontraction principle in partial metric spacesrdquo Mathematicaland Computer Modelling vol 55 no 5-6 pp 1673ndash1681 2012
[17] N Hussain H K Nashine Z Kadelburg and S M AlsulamildquoWeakly isotone increasingmappings and endpoints in partiallyordered metric spacesrdquo Journal of Inequalities and Applicationsvol 2012 article 232 2012
[18] NHussain DDJoric Z Kadelburg and S Radenovic ldquoSuzuki-type fixed point results in metric type spacesrdquo Fixed PointTheory and Applications vol 2012 article 126 2012
[19] N Hussain Z Kadelburg S Radenovic and F R Al-SolamyldquoComparison functions and fixed point results in partial metricspacesrdquo Abstract and Applied Analysis vol 2012 Article ID605781 15 pages 2012
[20] N Hussain and M Abbas ldquoCommon fixed point results fortwo new classes of hybrid pairs in symmetric spacesrdquo AppliedMathematics and Computation vol 218 no 2 pp 542ndash547 2011
[21] S Hong ldquoFixed points of multivalued operators in orderedmetric spaces with applicationsrdquo Nonlinear Analysis TheoryMethods amp Applications vol 72 no 11 pp 3929ndash3942 2010
[22] S Hong ldquoFixed points for mixed monotone multivalued oper-ators in Banach spaces with applicationsrdquo Journal of Mathemat-ical Analysis and Applications vol 337 no 1 pp 333ndash342 2008
[23] S Hong ldquoFixed points of discontinuous multivalued increasingoperators in Banach spaces with applicationsrdquo Journal of Math-ematical Analysis and Applications vol 282 no 1 pp 151ndash1622003
[24] M Imdad J Ali and M Tanveer ldquoCoincidence and commonfixed point theorems for nonlinear contractions in Menger PMspacesrdquo Chaos Solitons amp Fractals vol 42 no 5 pp 3121ndash31292009
[25] E Karapinar ldquoCiric type nonunique fixed point theorems onpartial metric spacesrdquo The Journal of Nonlinear Science andApplications vol 5 no 2 pp 74ndash83 2012
[26] E Karapnar and I M Erhan ldquoFixed point theorems for opera-tors on partial metric spacesrdquo Applied Mathematics Letters vol24 no 11 pp 1894ndash1899 2011
[27] E KarapinarMMarudai andV Pragadeeshwarar ldquoFixed pointtheorems for generalized weak contractions satisfying rationalexpressions on ordered Partial Metric Spacerdquo LobachevskiiJournal of Mathematics vol 34 no 1 pp 116ndash123 2013
[28] M S Khan M Swaleh and M Imdad Some Fixed PointTheorems IV Communications 1983
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Differential EquationsInternational Journal of
Volume 2014
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Journal of
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Complex AnalysisJournal of
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OptimizationJournal of
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International Journal of
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Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
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Algebra
Discrete Dynamics in Nature and Society
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Decision SciencesAdvances in
Discrete MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom
Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
Abstract and Applied Analysis 5
equal) Therefore the above condition fails to find commonfixed points of 119878 and 119879 This can be seen as
119889 (1198781 1198791) = 119889 ((1
16) (
5
17)) gt 120572119889 (1 1) = 0 (30)
However the same condition in partial metric space does notassert that 119878 = 119879 This can be seen as by taking the partialmetric same as in Example 10
119901 (1198781 1198791) = 119901 ((1
16) (
5
17)) =
5
17le 120572119901 (1 1) = 120572 (1)
(31)
for any 120572 ge 13 Hence Corollary 12 cannot be obtained froma metric fixed point theorem
Remark 14 By equating 120572 120573 120574 to 0 in all possible combi-nations one can derive a host of corollaries which includeMatthews theorem for mappings defined on a completepartial metric space
By taking 119878 = 119879 in the Theorem 9 we get the followingcorollary
Corollary 15 Let 119879 119883 rarr 119883 be a mapping on a completePMS (119883 119901) and 119909
0 119909 119910 isin 119883 and 119903 gt 0 Suppose that there
exist nonnegative reals 120572 120573 and 120574 such that 120572 + 120573 + 2120574 lt 1 If119879 satisfies
119901 (119879119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119879119909) 119901 (119910 119879119910) + 120574119901 (119910 119879119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(32)
for all 119909 119910 isin 119861119901(1199090 119903)
119901 (1199090 1198791199090) le (1 minus 120582) (119903 + 119901 (119909
0 1199090)) (33)
where 120582 = (120572+ 120574)(1 minus120573minus 120574) Then there exists a unique point119906 isin 119861
119901(1199090 119903) such that 119906 = 119879119906 Also 119901(119906 119906) = 0 Further 119879
has no fixed point other than 119906
By taking 119878 = 119879 in Corollary 11 we get the followingcorollary
Corollary 16 Let 119879 119883 rarr 119883 be a mapping on a completePMS (119883 119901) Suppose that there exist nonnegative reals 120572 120573and 120574 such that 120572 + 120573 + 2120574 lt 1 If 119879 satisfies
119901 (119879119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119879119909) 119901 (119910 119879119910) + 120574119901 (119910 119879119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(34)
for all 119909 119910 isin 119883 Then there exists a unique point 119906 isin 119883 suchthat 119906 = 119879119906 Also 119901(119906 119906) = 0 Further 119879 has no fixed pointother than 119906
Now we give an example in favour of Corollary 16
Example 17 Let 119883 = [0 4] endowed with the usual partialmetric 119901 defined by 119901(119909 119910) = max119909 119910 Clearly (119883 119901) is acomplete partial metric space Now we define 119865 119883 rarr 119883 asfollows
119865 (119909) =
119909
3if 0 le 119909 lt 2
119909
1 + 119909if 2 le 119909 le 4
(35)
for all 119909 isin 119883 Now let 119910 le 119909 If 119909 isin [0 2) (and so 119910 isin [0 2))Then 119901(119865119909 119865119910) = 1199093 119901(119909 119910) = 119909 119901(119909 119865119909) = 119909 119901(119910 119865119910) =
119910 119901(119910 119865119909) = 1199093 119901(119909 119865119910) = 119909 Taking 120572 = 13 120573 = 115120574 = 215 we can prove that all the conditions of Corollary 16are satisfied Now if 119909 isin [2 4] then 119901(119865119909 119865119910) = 119909(1 + 119909)119901(119909 119910) = 119909 119901(119909 119865119909) = 119909 119901(119910 119865119910) = 119910 119901(119910 119865119909) = 119909(1+119909)119901(119909 119865119910) = 119909 and taking 120572 = 13 120573 = 115 120574 = 215 onecan verify the condition of the above corollary Thus all theconditions of Corollary 16 are satisfied and 119906 = 0 is a fixedpoint of the mapping 119865
As an application of Theorem 9 we prove the followingtheorem for two finite families of mappings
Theorem 18 If 119879119894119898
1and 119878
119894119899
1are two pairwise commuting
finite families of self-mapping defined on a complete partialmetric space (119883 119901) such that the mappings 119878 and 119879 (with119879 = 119879
11198792sdot sdot sdot 119879119898and 119878 = 119878
11198782sdot sdot sdot 119878119899) satisfy the contractive
condition (5) then the component maps of the two families119879119894119898
1and 119878
119894119899
1have a unique common fixed point
Proof FromTheorem 9 we can say that the mappings 119879 and119878 have a unique common fixed point 119911 that is 119879119911 = 119878119911 = 119911Now our requirement is to show that 119911 is a common fixedpoint of all the component mappings of both the families Inviewof pairwise commutativity of the families 119879
119894119898
1and 119878
119894119899
1
(for every 1 le 119896 le 119898) we can write 119879119896119911 = 119879
119896119879119911 = 119879119879
119896119911 and
119879119896119911 = 119879119896119878119911 = 119878119879
119896119911 which show that 119879
119896119911 (for every 119896) is also
a common fixed point of 119879 and 119878 By using the uniqueness ofcommonfixed point we canwrite119879
119896119911 = 119911 (for every 119896) which
shows that 119911 is a common fixed point of the family 119879119894119898
1
Using the same argument one can also show that (for every1 le 119896 le 119899) 119878
119896119911 = 119911Thus componentmaps of the two families
119879119894119898
1and 119878
119894119899
1have a unique common fixed point
By setting 1198791= 1198792= sdot sdot sdot = 119879
119898= 119865 and 119878
1= 1198782= sdot sdot sdot =
119878119899= 119866 in Theorem 18 we get the following corollary
Corollary 19 Let 119865 119866 119883 rarr 119883 be two commuting self-mappings defined on a complete PMS (119883 119901) satisfying thecondition
119901 (119865119898119909 119866119899119910)
le 120572119901 (119909 119910)
+120573119901 (119909 119865
119898119909) 119901 (119910 119866
119899119910) + 120574119901 (119910 119865
119898119909) 119901 (119909 119866
119899119910)
1 + 119901 (119909 119910)
(36)
6 Abstract and Applied Analysis
for all 119909 119910 isin 119883 120572 + 120573 + 2120574 lt 1 (120572 120573 and 120574 are nonnegativereals) Then F and G have a unique common fixed point
By setting 119898 = 119899 and 119865 = 119866 = 119879 in Corollary 19 wededuce the following corollary
Corollary 20 Let 119879 119883 rarr 119883 be a mapping defined on acomplete PMS (119883 119901) satisfying the condition
119901 (119879119899119909 119879119899119910)
le 120572119901 (119909 119910)
+120573119901 (119909 119879
119899119909) 119901 (119910 119879
119899119910) + 120574119901 (119910 119879
119899119909) 119901 (119909 119879
119899119910)
1 + 119901 (119909 119910)
(37)
for all 119909 119910 isin 119883 120572 + 120573 + 2120574 lt 1 (120572 120573 and 120574 are nonnegativereals) Then F has a unique fixed point
By setting 120573 = 120574 = 0 we draw following corollary whichcan be viewed as an extension of Bryantrsquos theorem [15] for amapping on a complete PMS (119883 119901)
Corollary 21 Let 119865 119883 rarr 119883 be a mapping on a completePMS (119883 119901) If 119865 satisfies
119901 (119865119899119909 119865119899119910) le 120572119901 (119909 119910) (38)
for all 119909 119910 isin 119883 120572 lt 1 Then 119865 has a unique fixed point
The following example demonstrates the superiority ofBryantrsquos theorem overMatthews theorem on complete partialmetric space
Example 22 Let119883 = [0 4] Define the partial metric 119901 119883 times
119883 rarr R by
119901 (119909 119910) = max 119909 119910 (39)
Then (119883 119901) is a complete partial metric space Let 119865 119883 rarr
119883 be defined as follows
119865 (119909) =
1199092 if 119909 isin [0 1 [
2 if 119909 isin [1 2 [
0 if 119909 isin [2 4]
(40)
Then for 119909 = 0 and 119910 = 1 we get
119901 (119865 (0) 119865 (1)) = 119901 (0 2) = 2 gt 120572119901 (0 1) = 120572 (1) (41)
because 0 le 120572 lt 1 However 1198652 satisfies the requirement ofBryantrsquos theorem and 119911 = 0 is the unique fixed point of 119865
3 Results for Set Valued Mappings
Theorem23 Let (119883 119901) be a complete partial metric space andlet 119878 119879 119883 rarr 119862119861
119901(119883) be mappings such that
119867119901(119878119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119878119909) 119901 (119910 119879119910) + 120574119901 (119910 119878119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(42)
for all 119909 119910 isin 119883 0 le 120572 120573 120574 with 120572 + 120573 + 2120574 lt 1 Then 119878 and 119879
have a common fixed point
Proof Assume that119872 = ((120572 + 120574)(1 minus 120573 minus 120574)) Let 1199090isin 119883 be
arbitrary but fixed element of 119883 and choose 1199091
isin 119878(1199090) By
Lemma 8 we can choose 1199092isin 119879(119909
1) such that
119901 (1199091 1199092) le 119867
119901(119878 (1199090) 119879 (119909
1)) + (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1198781199090) 119901 (119909
1 1198791199091)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199091 1198781199090) 119901 (119909
0 1198791199091)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1199091) 119901 (119909
1 1199092)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199091 1199091) 119901 (119909
0 1199092)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1199091) 119901 (119909
1 1199092)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199090 1199091) 119901 (119909
0 1199092)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573119901 (119909
1 1199092) + 120574119901 (119909
0 1199092)
+ (120572 + 120574)
(43)
So we get
119901 (1199091 1199092) le (
120572 + 120574
1 minus 120573 minus 120574)119901 (119909
0 1199091) + (
120572 + 120574
1 minus 120573 minus 120574) (44)
Since119872 = ((120572 + 120574)(1 minus 120573 minus 120574)) so it further implies that119901 (1199091 1199092) le 119872119901 (119909
0 1199091) + 119872 (45)
By Lemma 8 we can choose 1199093isin 119878(1199092) such that
119901 (1199092 1199093) le 119867
119901(119879 (1199091) 119878 (119909
2)) +
(120572 + 120574)2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1198791199091) 119901 (119909
2 1198781199092)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199092 1198791199091) 119901 (119909
1 1198781199092)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199092 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199091 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
Abstract and Applied Analysis 7
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199091 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573119901 (119909
2 1199093) + 120574119901 (119909
1 1199093)
+(120572 + 120574)
2
1 minus 120573 minus 120574
(46)
So we get
119901 (1199092 1199093) le (
120572 + 120574
1 minus 120573 minus 120574)
2
119901 (1199090 1199091) + 2(
120572 + 120574
1 minus 120573 minus 120574)
2
(47)
Continuing in this manner one can obtain a sequence 119909119899 in
119883 as 1199092119899+1
isin 119878(1199092119899) and 119909
2119899+2isin 119879(119909
2119899+1) such that
119901 (119909119899 119909119899+1
) le 119872119901 (119909119899minus1
119909119899) + 119872
le sdot sdot sdot le 119872119899119901 (1199090 1199091) + 119899119872
119899
(48)
where 119872 = ((120572 + 120573)(1 minus 120572)) lt 1 for all 119899 ge 0 Without lossof generality assume that 119899 gt 119898 Then using (48) and thetriangle inequality for partial metrics (P
4) we have
119901 (119909119899 119909119898)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119899+2
) + sdot sdot sdot + 119901 (119909119898minus1
119909119898)
le 119872119899119901 (1199090 1199091) + 119899119872
119899+ 119872119899+1
119901 (1199090 1199091)
+ (119899 + 1)119872119899+1
+ sdot sdot sdot + 119872119898minus1
119901 (1199090 1199091)
+ (119898 minus 1)119872119898minus1
le
119898minus1
sum
119894=119899
119872119894119901 (1199090 1199091)
+
119898minus1
sum
119894=119899
119894119872119894997888rarr 0 as 119899 997888rarr +infin (since 0 lt 119872 lt 1)
(49)
By the definition of 119901119904 we get
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (50)
This yields that 119909119899 is a Cauchy sequence in (119883 119901
119904) Since
(119883 119901) is complete then from Lemma 2(4) (119883 119901119904) is a com-
plete metric space Therefore the sequence 119909119899 converges
to some 119909lowast
isin 119883 with respect to the metric 119901119904 that is
lim119899rarr+infin
119901119904(119909119899 119909lowast) = 0 Again from Lemma 2(4) we get
119901 (119909lowast 119909lowast) = lim119899rarr+infin
119901 (119909119899 119909lowast) = lim119899rarr+infin
119901 (119909119899 119909119899) = 0 (51)
119867119901(119879 (1199092119899+2
) 119878 (119909lowast))
le 120572119901 (1199092119899+2
119909lowast)
+ 120573119901 (1199092119899+2
119879 (1199092119899+2
)) 119901 (119909lowast 119878 (119909lowast))
1 + 119901 (1199092119899+2
119909lowast)
+ 120574119901 (1199092119899+2
119878 (119909lowast)) 119901 (119909
lowast 119879 (1199092119899+2
))
1 + 119901 (1199092119899+2
119909lowast)
le 120572119901 (1199092119899+2
119909lowast)
+ 120573119901 (1199092119899+2
1199092119899+3
) 119901 (119909lowast 119878 (119909lowast))
1 + 119901 (1199092119899+2
119909lowast)
+ 120574119901 (1199092119899+2
119878 (119909lowast)) 119901 (119909
lowast 1199092119899+1
)
1 + 119901 (1199092119899+2
119909lowast)
(52)
taking limit as 119899 rarr infin and using (51) we get
lim119899rarr+infin
119867119901(119879 (1199092119899+2
) 119878 (119909lowast)) = 0 (53)
Now 1199092119899+1
isin 119879(1199092119899+2
) gives that
119901 (1199092119899+1
119878 (119909lowast)) le 119867
119901(119879 (1199092119899+2
) 119878 (119909lowast)) (54)
which implies that
lim119899rarr+infin
119901 (1199092119899+1
119878 (119909lowast)) = 0 (55)
On the other hand by (P4) we have
119901 (119909lowast 119878 (119909lowast)) le 119901 (119909
lowast 1199092119899+2
) + 119901 (1199092119899+2
119878 (119909lowast))
minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (119909lowast 1199092119899+2
) + 119901 (1199092119899+2
119878 (119909lowast))
(56)
Taking limit as 119899 rarr +infin and using (51) and (55) we obtain119901(119909lowast 119878(119909lowast)) = 0 Therefore from (51) (119901(119909lowast 119909lowast) = 0) we
obtain
119901 (119909lowast 119878 (119909lowast)) = 119901 (119909
lowast 119909lowast) (57)
which from Remark 14 implies that 119909lowast
isin 119878(119909lowast) = 119878(119909lowast)
Similarly one can easily prove that 119909lowast isin 119879(119909lowast) Thus 119878 and
119879 have a common fixed point
Remark 24 For 120573 = 120574 = 0 and 119878 = 119879 Theorem 23 reduces tothe following result of Aydi et al [9]
Corollary 25 (see [9 Theorem 32]) Let (119883 119901) be a partialmetric space If 119879 119883 rarr 119862119861
119901(119883) is a multivalued mapping
such that for all 119909 119910 isin 119883 one has
119867119901(119879119909 119879119910) le 119896119901 (119886 119887) (58)
where 119896 isin (0 1) Then 119879 has a fixed point
8 Abstract and Applied Analysis
Theorem26 Let (119883 119901) be a complete partialmetric space and119878 119879 119883 rarr 119862119861
119901(119883) be multivalued mappings such that
119867119901(119878119909 119879119910) le 120572
119901 (119909 119878119909) 119901 (119909 119879119910) + 119901 (119910 119879119910) 119901 (119910 119878119909)
119901 (119909 119879119910) + 119901 (119910 119878119909)
+ 120573119889 (119909 119910)
(59)
for all 119909 119910 isin 119883 0 le 120572 120573 with 2120572 + 120573 lt 1 and 119901(119909 119879119910) +
119901(119910 119878119909) = 0 Then 119878 and 119879 have a common fixed point
Proof Assume that 119897 = (120572+120573)(1minus120572) Let 1199090isin 119883 be arbitrary
but fixed element of119883 and choose 1199091isin 119878(1199090)
When 119901(119909 119879119910)+119901(119910 119878119909) = 0 By Lemma 8we can choose1199092isin 119879(119909
1) such that
119901 (1199091 1199092)
le 119867119901(119878 (1199090) 119879 (119909
1)) + (120572 + 120573)
le 120572119901 (1199090 1198781199090) 119901 (119909
0 1198791199091) + 119901 (119909
1 1198791199091) 119901 (119909
1 1198781199090)
119901 (1199090 1198791199091) + 119901 (119909
1 1198781199090)
+ 120573119901 (1199090 1199091) + (120572 + 120573)
le 120572119901 (1199090 1199091) 119901 (119909
0 1199092) + 119901 (119909
1 1199092) 119901 (119909
1 1199091)
119901 (1199090 1199092) + 119901 (119909
1 1199091)
+ 120573119901 (1199090 1199091) + (120572 + 120573)
le 120572 119901 (1199090 1199091) + 119901 (119909
1 1199092) + 120573119901 (119909
0 1199091) + (120572 + 120573)
(60)
because 119901(1199090 1199092) lt 119901(119909
0 1199092) + 119901(119909
1 1199091) and 119901(119909
1 1199091) lt
119901(1199091 1199091) + 119901(119909
0 1199092) Thus we get
119901 (1199091 1199092) le (
120572 + 120573
1 minus 120572)119901 (119909
0 1199091) + (
120572 + 120573
1 minus 120572) (61)
It further implies that
119901 (1199091 1199092) le 119897119901 (119909
0 1199091) + 119897 (62)
By Lemma 8 we can choose 1199093isin 119878(1199092) such that
119901 (1199092 1199093)
le 119867119901(119879 (1199091) 119878 (119909
2)) +
(120572 + 120573)2
1 minus 120572
le 120572119901 (1199091 1198791199091) 119901 (119909
1 1198781199092) + 119901 (119909
2 1198781199092) 119901 (119909
2 1198791199091)
119901 (1199091 1198781199092) + 119901 (119909
2 1198791199091)
+ 120573119901 (1199091 1199092) +
(120572 + 120573)2
1 minus 120572
le 120572119901 (1199091 1199092) 119901 (119909
1 1199093) + 119901 (119909
2 1199093) 119901 (119909
2 1199092)
119901 (1199091 1199093) + 119901 (119909
2 1199092)
+ 120573119901 (1199091 1199092) +
(120572 + 120573)2
1 minus 120572
le 120572 119901 (1199091 1199092) + 119901 (119909
2 1199093) + 120573119901 (119909
1 1199092) +
(120572 + 120573)2
1 minus 120572
(63)
because 119901(1199091 1199093) lt 119901(119909
1 1199093) + 119901(119909
2 1199092) and 119901(119909
2 1199092) lt
119901(1199092 1199092) + 119901(119909
1 1199093) Thus we get
119901 (1199092 1199093) le (
120572 + 120573
1 minus 120572)119901 (119909
1 1199092) + (
120572 + 120573
1 minus 120572)
2
(64)
It further implies that
119901 (1199092 1199093) le 1198972119901 (1199090 1199090) + 21198972 (65)
Continuing in this manner one can obtain a sequence 119909119899 in
119883 as 1199092119899+1
isin 119878(1199092119899) and 119909
2119899+2isin 119879(119909
2119899+1) such that
119901 (119909119899 119909119899+1
) le 119897119901 (119909119899minus1
119909119899) + 119897 le sdot sdot sdot le 119897
119899119901 (1199090 1199091) + 119899119897119899
(66)
where 119897 = ((120572 + 120573)(1 minus 120572)) lt 1 for all 119899 ge 0 Withoutloss of generality assume that 119898 gt 119899 Then using (66) andthe triangle inequality for partial metrics (P
4) one can easily
prove that
119901 (119909119899 119909119898) le
119898minus1
sum
119894=119899
119897119894119901 (1199090 1199091) +
119898minus1
sum
119894=119899
119894119897119894
997888rarr 0 as 119899 997888rarr +infin (since 0 lt 119897 lt 1)
(67)
By the definition of 119901119904
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (68)
This yields that 119909119899 is a Cauchy sequence in (119883 119901
119904) Since
(119883 119901) is complete then from Lemma 2(4) (119883 119901119904) is a com-
plete metric space Therefore the sequence 119909119899 converges
to some 1199091015840
isin 119883 with respect to the metric 119901119904 that is
lim119899rarr+infin
119901119904(119909119899 1199091015840) = 0 Again from Lemma 2(4) we get
119901 (1199091015840 1199091015840) = lim119899rarr+infin
119901 (119909119899 119909) = lim119899rarr+infin
119901 (119909119899 119909119899) = 0
(69)
Abstract and Applied Analysis 9
119867119901(119879 (1199092119899+1
) 119878 (1199091015840))
le 120572 (119901 (1199092119899+1
119879 (1199092119899+1
)) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 119879 (1199092119899+1
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 119879 (1199092119899+1
)))minus1
+ 120573119901 (1199092119899+1
119909)
le 120572 (119901 ((1199092119899+1
1199092119899+2
) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 1199092119899+2
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 1199092119899+2
))minus1
+ 120573119901 (1199092119899+1
119909)
(70)
therefore
lim119899rarr+infin
119867119901(119879 (1199092119899+1
) 119878 (1199091015840)) = 0 (71)
Now 1199092119899+2
isin 119879(1199092119899+1
) gives that
119901 (1199092119899+2
119878 (1199091015840)) le 119867
119901(119879 (1199092119899+1
) 119878 (1199091015840)) (72)
which implies that
lim119899rarr+infin
119901 (1199092119899+2
119878 (1199091015840)) = 0 (73)
On the other hand we have
119901 (1199091015840 119878 (1199091015840)) le 119901 (119909
1015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (1199091015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
(74)
Taking limit as 119899 rarr +infin and using (69) and (73) we obtain119901(1199091015840 119878(1199091015840)) = 0 Therefore from (69) (119901(1199091015840 1199091015840) = 0) we
obtain
119901 (1199091015840 119878 (1199091015840)) = 119901 (119909
1015840 1199091015840) (75)
which from Remark 14 implies that 1199091015840
isin 119878(1199091015840) = 119878(1199091015840)
It follows similarly that 1199091015840
isin 119879(1199091015840) Thus 119878 and 119879 have a
common fixed point
Now we give an example which illustrates our Theo-rem 26
Example 27 Let 119883 = 1 2 3 be endowed with usual orderand let 119901 be a partial metric on119883 defined as
119901 (1 1) = 119901 (2 2) = 0 119901 (3 3) =5
11
119901 (1 2) = 119901 (2 1) =3
10
119901 (1 3) = 119901 (3 1) =9
20
119901 (2 3) = 119901 (3 2) =1
2
(76)
Define the mappings 119878 119879 119883 rarr 119862119861119901(119883) by
119878119909 = 1 if 119909 119910 isin 1 2
1 2 otherwise
119879119909 = 1 if 119909 119910 isin 1 2
2 otherwise
(77)
Note that 119878119909 and 119879119909 are closed and bounded for all 119909 isin 119883
with respect to the partial metric 119901 To show that for all 119909 119910in119883 (59) is satisfied with 120572 = 111 120573 = 45 we consider thefollowing cases if 119909 119910 isin 1 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 1) = 0 (78)
and condition (59) is satisfied obviously
If 119909 = 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 2) =
3
10
119901 (119909 119878119909) = 119901 (119910 119878119909) = 119901 (3 1 2) =9
20
119901 (119909 119879119910) = 119901 (119910 119879119910) = 119901 (119910 119878119909) = 119901 (3 2) =11
24
119901 (119909 119910) = 119901 (3 3) =5
11
(79)
If 119909 = 3 119910 = 1 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (1 1) = 0 119901 (119910 119878119909) = 119901 (1 1 2) = 0
119901 (119909 119910) = 119901 (3 1) =9
20
(80)
10 Abstract and Applied Analysis
If 119909 = 3 119910 = 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (2 1) =3
10 119901 (119910 119878119909) = 119901 (2 1 2) = 0
119901 (119909 119910) = 119901 (3 2) =1
2
(81)
If 119909 = 1 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (1 1) = 0 119901 (119909 119879119910) = 119901 (1 2) =3
10
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (1 3) =9
20
(82)
If 119909 = 2 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (2 1) =3
10 119901 (119909 119879119910) = 119901 (2 2) = 0
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (2 3) =1
2
(83)
Thus all the conditions ofTheorem 26 are satisfied Here 119909 =
1 is a common fixed point of 119878 and 119879On the other hand the metric 119901
119904 induced by the partialmetric 119901 is given by
119901119904(1 1) = 119901
119904(2 2) = 119901
119904(3 3) = 0
119901119904(2 1) = 119901
119904(2 1) =
3
4
119901119904(3 2) = 119901
119904(2 3) =
4
7
119901119904(3 1) = 119901
119904(1 3) =
14
29
(84)
Note that in case of ordinary Hausdorff metric given map-ping does not satisfy the condition Indeed for 119909 = 1 and119910 = 3 we have
119867(119878119909 119879119910) = 119867 (1 2) =3
4
119901119904(119909 119878119909) = 119901
119904(1 1) = 0
119901119904(119909 119879119910) = 119901
119904(1 2) =
3
4
119901119904(119910 119879119910) = 119901
119904(3 2) =
4
7
119901119904(119910 119878119909) = 119901
119904(3 1) =
14
29
(85)
for the values of 120572 = 111 120573 = 45 By a routine calculationone can easily verify that the mapping does not satisfy thecondition which involved ordinary Hausdorff metric
Acknowledgment
This paper was funded by the Deanship of Scientific Research(DSR) King Abdulaziz University Jeddah The authorstherefore acknowledge with thanks DSR technical and finan-cial support
References
[1] S G Matthews ldquoPartial metric topologyrdquo in Proceedings of the8th Summer Conference on General Topology and Applicationsvol 728 pp 183ndash197 New York Academy of Science 1994
[2] T Abdeljawad E Karapinar andK Tas ldquoA generalized contrac-tion principle with control functions on partial metric spacesrdquoComputers amp Mathematics with Applications vol 63 no 3 pp716ndash719 2012
[3] T Abdeljawad ldquoFixed points for generalized weakly contractivemappings in partialmetric spacesrdquoMathematical andComputerModelling vol 54 no 11-12 pp 2923ndash2927 2011
[4] J Ahmad M Arshad and C Vetro ldquoOn a theorem of Khan in ageneralized metric spacerdquo International Journal of Analysis vol2013 Article ID 852727 6 pages 2013
[5] S Alsulami N Hussain and A Alotaibi ldquoCoupled fixed andcoincidence points for monotone operators in partial metricspacesrdquo Fixed Point Theory and Applications vol 2012 article173 2012
[6] I Altun and A Erduran ldquoFixed point theorems for monotonemappings on partial metric spacesrdquo Fixed Point Theory andApplications vol 2011 Article ID 508730 2011
[7] M Arshad J Ahmad and E Karapinar ldquoSome common fixedpoint results in rectangularmetric spacesrdquo International Journalof Analysis vol 2013 Article ID 307234 7 pages 2013
[8] M Arshad E Karapinar and J Ahmad ldquoSome unique fixedpoint theorem for rational contractions in partially orderedmetric spacesrdquo Journal of Inequalities andApplications vol 2013article 248 2013
[9] H Aydi M Abbas and C Vetro ldquoPartial Hausdorff metric andNadlerrsquos fixed point theorem on partial metric spacesrdquo Topologyand Its Applications vol 159 no 14 pp 3234ndash3242 2012
Abstract and Applied Analysis 11
[10] H Aydi M Abbas and C Vetro ldquoCommon Fixed points formultivalued generalized contractions on partial metric spacesrdquoRevista de la Real Academia de Ciencias Exactas Fisicas yNaturales A 2013
[11] A Azam and M Arshad ldquoFixed points of a sequence of locallycontractive multivalued mapsrdquo Computers amp Mathematics withApplications vol 57 no 1 pp 96ndash100 2009
[12] A Azam B Fisher and M Khan ldquoCommon fixed point the-orems in complex valued metric spacesrdquo Numerical FunctionalAnalysis and Optimization vol 32 no 3 pp 243ndash253 2011
[13] S Banach ldquoSur les operations dans les ensembles abstraitset leurs applications aux equations integralesrdquo FundamentaMathematicae vol 3 pp 133ndash181 1922
[14] I Beg and A Azam ldquoFixed points of asymptotically regularmultivalued mappingsrdquo Journal of the Australian MathematicalSociety A vol 53 no 3 pp 313ndash326 1992
[15] V W Bryant ldquoA remark on a fixed-point theorem for iteratedmappingsrdquo The American Mathematical Monthly vol 75 pp399ndash400 1968
[16] K P Chi E Karapınar and T D Thanh ldquoA generalizedcontraction principle in partial metric spacesrdquo Mathematicaland Computer Modelling vol 55 no 5-6 pp 1673ndash1681 2012
[17] N Hussain H K Nashine Z Kadelburg and S M AlsulamildquoWeakly isotone increasingmappings and endpoints in partiallyordered metric spacesrdquo Journal of Inequalities and Applicationsvol 2012 article 232 2012
[18] NHussain DDJoric Z Kadelburg and S Radenovic ldquoSuzuki-type fixed point results in metric type spacesrdquo Fixed PointTheory and Applications vol 2012 article 126 2012
[19] N Hussain Z Kadelburg S Radenovic and F R Al-SolamyldquoComparison functions and fixed point results in partial metricspacesrdquo Abstract and Applied Analysis vol 2012 Article ID605781 15 pages 2012
[20] N Hussain and M Abbas ldquoCommon fixed point results fortwo new classes of hybrid pairs in symmetric spacesrdquo AppliedMathematics and Computation vol 218 no 2 pp 542ndash547 2011
[21] S Hong ldquoFixed points of multivalued operators in orderedmetric spaces with applicationsrdquo Nonlinear Analysis TheoryMethods amp Applications vol 72 no 11 pp 3929ndash3942 2010
[22] S Hong ldquoFixed points for mixed monotone multivalued oper-ators in Banach spaces with applicationsrdquo Journal of Mathemat-ical Analysis and Applications vol 337 no 1 pp 333ndash342 2008
[23] S Hong ldquoFixed points of discontinuous multivalued increasingoperators in Banach spaces with applicationsrdquo Journal of Math-ematical Analysis and Applications vol 282 no 1 pp 151ndash1622003
[24] M Imdad J Ali and M Tanveer ldquoCoincidence and commonfixed point theorems for nonlinear contractions in Menger PMspacesrdquo Chaos Solitons amp Fractals vol 42 no 5 pp 3121ndash31292009
[25] E Karapinar ldquoCiric type nonunique fixed point theorems onpartial metric spacesrdquo The Journal of Nonlinear Science andApplications vol 5 no 2 pp 74ndash83 2012
[26] E Karapnar and I M Erhan ldquoFixed point theorems for opera-tors on partial metric spacesrdquo Applied Mathematics Letters vol24 no 11 pp 1894ndash1899 2011
[27] E KarapinarMMarudai andV Pragadeeshwarar ldquoFixed pointtheorems for generalized weak contractions satisfying rationalexpressions on ordered Partial Metric Spacerdquo LobachevskiiJournal of Mathematics vol 34 no 1 pp 116ndash123 2013
[28] M S Khan M Swaleh and M Imdad Some Fixed PointTheorems IV Communications 1983
Submit your manuscripts athttpwwwhindawicom
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Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Algebra
Discrete Dynamics in Nature and Society
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Decision SciencesAdvances in
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Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
6 Abstract and Applied Analysis
for all 119909 119910 isin 119883 120572 + 120573 + 2120574 lt 1 (120572 120573 and 120574 are nonnegativereals) Then F and G have a unique common fixed point
By setting 119898 = 119899 and 119865 = 119866 = 119879 in Corollary 19 wededuce the following corollary
Corollary 20 Let 119879 119883 rarr 119883 be a mapping defined on acomplete PMS (119883 119901) satisfying the condition
119901 (119879119899119909 119879119899119910)
le 120572119901 (119909 119910)
+120573119901 (119909 119879
119899119909) 119901 (119910 119879
119899119910) + 120574119901 (119910 119879
119899119909) 119901 (119909 119879
119899119910)
1 + 119901 (119909 119910)
(37)
for all 119909 119910 isin 119883 120572 + 120573 + 2120574 lt 1 (120572 120573 and 120574 are nonnegativereals) Then F has a unique fixed point
By setting 120573 = 120574 = 0 we draw following corollary whichcan be viewed as an extension of Bryantrsquos theorem [15] for amapping on a complete PMS (119883 119901)
Corollary 21 Let 119865 119883 rarr 119883 be a mapping on a completePMS (119883 119901) If 119865 satisfies
119901 (119865119899119909 119865119899119910) le 120572119901 (119909 119910) (38)
for all 119909 119910 isin 119883 120572 lt 1 Then 119865 has a unique fixed point
The following example demonstrates the superiority ofBryantrsquos theorem overMatthews theorem on complete partialmetric space
Example 22 Let119883 = [0 4] Define the partial metric 119901 119883 times
119883 rarr R by
119901 (119909 119910) = max 119909 119910 (39)
Then (119883 119901) is a complete partial metric space Let 119865 119883 rarr
119883 be defined as follows
119865 (119909) =
1199092 if 119909 isin [0 1 [
2 if 119909 isin [1 2 [
0 if 119909 isin [2 4]
(40)
Then for 119909 = 0 and 119910 = 1 we get
119901 (119865 (0) 119865 (1)) = 119901 (0 2) = 2 gt 120572119901 (0 1) = 120572 (1) (41)
because 0 le 120572 lt 1 However 1198652 satisfies the requirement ofBryantrsquos theorem and 119911 = 0 is the unique fixed point of 119865
3 Results for Set Valued Mappings
Theorem23 Let (119883 119901) be a complete partial metric space andlet 119878 119879 119883 rarr 119862119861
119901(119883) be mappings such that
119867119901(119878119909 119879119910) le 120572119901 (119909 119910)
+120573119901 (119909 119878119909) 119901 (119910 119879119910) + 120574119901 (119910 119878119909) 119901 (119909 119879119910)
1 + 119901 (119909 119910)
(42)
for all 119909 119910 isin 119883 0 le 120572 120573 120574 with 120572 + 120573 + 2120574 lt 1 Then 119878 and 119879
have a common fixed point
Proof Assume that119872 = ((120572 + 120574)(1 minus 120573 minus 120574)) Let 1199090isin 119883 be
arbitrary but fixed element of 119883 and choose 1199091
isin 119878(1199090) By
Lemma 8 we can choose 1199092isin 119879(119909
1) such that
119901 (1199091 1199092) le 119867
119901(119878 (1199090) 119879 (119909
1)) + (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1198781199090) 119901 (119909
1 1198791199091)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199091 1198781199090) 119901 (119909
0 1198791199091)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1199091) 119901 (119909
1 1199092)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199091 1199091) 119901 (119909
0 1199092)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573
119901 (1199090 1199091) 119901 (119909
1 1199092)
1 + 119901 (1199090 1199091)
+ 120574119901 (1199090 1199091) 119901 (119909
0 1199092)
1 + 119901 (1199090 1199091)
+ (120572 + 120574)
le 120572119901 (1199090 1199091) + 120573119901 (119909
1 1199092) + 120574119901 (119909
0 1199092)
+ (120572 + 120574)
(43)
So we get
119901 (1199091 1199092) le (
120572 + 120574
1 minus 120573 minus 120574)119901 (119909
0 1199091) + (
120572 + 120574
1 minus 120573 minus 120574) (44)
Since119872 = ((120572 + 120574)(1 minus 120573 minus 120574)) so it further implies that119901 (1199091 1199092) le 119872119901 (119909
0 1199091) + 119872 (45)
By Lemma 8 we can choose 1199093isin 119878(1199092) such that
119901 (1199092 1199093) le 119867
119901(119879 (1199091) 119878 (119909
2)) +
(120572 + 120574)2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1198791199091) 119901 (119909
2 1198781199092)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199092 1198791199091) 119901 (119909
1 1198781199092)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199092 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199091 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
Abstract and Applied Analysis 7
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199091 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573119901 (119909
2 1199093) + 120574119901 (119909
1 1199093)
+(120572 + 120574)
2
1 minus 120573 minus 120574
(46)
So we get
119901 (1199092 1199093) le (
120572 + 120574
1 minus 120573 minus 120574)
2
119901 (1199090 1199091) + 2(
120572 + 120574
1 minus 120573 minus 120574)
2
(47)
Continuing in this manner one can obtain a sequence 119909119899 in
119883 as 1199092119899+1
isin 119878(1199092119899) and 119909
2119899+2isin 119879(119909
2119899+1) such that
119901 (119909119899 119909119899+1
) le 119872119901 (119909119899minus1
119909119899) + 119872
le sdot sdot sdot le 119872119899119901 (1199090 1199091) + 119899119872
119899
(48)
where 119872 = ((120572 + 120573)(1 minus 120572)) lt 1 for all 119899 ge 0 Without lossof generality assume that 119899 gt 119898 Then using (48) and thetriangle inequality for partial metrics (P
4) we have
119901 (119909119899 119909119898)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119899+2
) + sdot sdot sdot + 119901 (119909119898minus1
119909119898)
le 119872119899119901 (1199090 1199091) + 119899119872
119899+ 119872119899+1
119901 (1199090 1199091)
+ (119899 + 1)119872119899+1
+ sdot sdot sdot + 119872119898minus1
119901 (1199090 1199091)
+ (119898 minus 1)119872119898minus1
le
119898minus1
sum
119894=119899
119872119894119901 (1199090 1199091)
+
119898minus1
sum
119894=119899
119894119872119894997888rarr 0 as 119899 997888rarr +infin (since 0 lt 119872 lt 1)
(49)
By the definition of 119901119904 we get
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (50)
This yields that 119909119899 is a Cauchy sequence in (119883 119901
119904) Since
(119883 119901) is complete then from Lemma 2(4) (119883 119901119904) is a com-
plete metric space Therefore the sequence 119909119899 converges
to some 119909lowast
isin 119883 with respect to the metric 119901119904 that is
lim119899rarr+infin
119901119904(119909119899 119909lowast) = 0 Again from Lemma 2(4) we get
119901 (119909lowast 119909lowast) = lim119899rarr+infin
119901 (119909119899 119909lowast) = lim119899rarr+infin
119901 (119909119899 119909119899) = 0 (51)
119867119901(119879 (1199092119899+2
) 119878 (119909lowast))
le 120572119901 (1199092119899+2
119909lowast)
+ 120573119901 (1199092119899+2
119879 (1199092119899+2
)) 119901 (119909lowast 119878 (119909lowast))
1 + 119901 (1199092119899+2
119909lowast)
+ 120574119901 (1199092119899+2
119878 (119909lowast)) 119901 (119909
lowast 119879 (1199092119899+2
))
1 + 119901 (1199092119899+2
119909lowast)
le 120572119901 (1199092119899+2
119909lowast)
+ 120573119901 (1199092119899+2
1199092119899+3
) 119901 (119909lowast 119878 (119909lowast))
1 + 119901 (1199092119899+2
119909lowast)
+ 120574119901 (1199092119899+2
119878 (119909lowast)) 119901 (119909
lowast 1199092119899+1
)
1 + 119901 (1199092119899+2
119909lowast)
(52)
taking limit as 119899 rarr infin and using (51) we get
lim119899rarr+infin
119867119901(119879 (1199092119899+2
) 119878 (119909lowast)) = 0 (53)
Now 1199092119899+1
isin 119879(1199092119899+2
) gives that
119901 (1199092119899+1
119878 (119909lowast)) le 119867
119901(119879 (1199092119899+2
) 119878 (119909lowast)) (54)
which implies that
lim119899rarr+infin
119901 (1199092119899+1
119878 (119909lowast)) = 0 (55)
On the other hand by (P4) we have
119901 (119909lowast 119878 (119909lowast)) le 119901 (119909
lowast 1199092119899+2
) + 119901 (1199092119899+2
119878 (119909lowast))
minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (119909lowast 1199092119899+2
) + 119901 (1199092119899+2
119878 (119909lowast))
(56)
Taking limit as 119899 rarr +infin and using (51) and (55) we obtain119901(119909lowast 119878(119909lowast)) = 0 Therefore from (51) (119901(119909lowast 119909lowast) = 0) we
obtain
119901 (119909lowast 119878 (119909lowast)) = 119901 (119909
lowast 119909lowast) (57)
which from Remark 14 implies that 119909lowast
isin 119878(119909lowast) = 119878(119909lowast)
Similarly one can easily prove that 119909lowast isin 119879(119909lowast) Thus 119878 and
119879 have a common fixed point
Remark 24 For 120573 = 120574 = 0 and 119878 = 119879 Theorem 23 reduces tothe following result of Aydi et al [9]
Corollary 25 (see [9 Theorem 32]) Let (119883 119901) be a partialmetric space If 119879 119883 rarr 119862119861
119901(119883) is a multivalued mapping
such that for all 119909 119910 isin 119883 one has
119867119901(119879119909 119879119910) le 119896119901 (119886 119887) (58)
where 119896 isin (0 1) Then 119879 has a fixed point
8 Abstract and Applied Analysis
Theorem26 Let (119883 119901) be a complete partialmetric space and119878 119879 119883 rarr 119862119861
119901(119883) be multivalued mappings such that
119867119901(119878119909 119879119910) le 120572
119901 (119909 119878119909) 119901 (119909 119879119910) + 119901 (119910 119879119910) 119901 (119910 119878119909)
119901 (119909 119879119910) + 119901 (119910 119878119909)
+ 120573119889 (119909 119910)
(59)
for all 119909 119910 isin 119883 0 le 120572 120573 with 2120572 + 120573 lt 1 and 119901(119909 119879119910) +
119901(119910 119878119909) = 0 Then 119878 and 119879 have a common fixed point
Proof Assume that 119897 = (120572+120573)(1minus120572) Let 1199090isin 119883 be arbitrary
but fixed element of119883 and choose 1199091isin 119878(1199090)
When 119901(119909 119879119910)+119901(119910 119878119909) = 0 By Lemma 8we can choose1199092isin 119879(119909
1) such that
119901 (1199091 1199092)
le 119867119901(119878 (1199090) 119879 (119909
1)) + (120572 + 120573)
le 120572119901 (1199090 1198781199090) 119901 (119909
0 1198791199091) + 119901 (119909
1 1198791199091) 119901 (119909
1 1198781199090)
119901 (1199090 1198791199091) + 119901 (119909
1 1198781199090)
+ 120573119901 (1199090 1199091) + (120572 + 120573)
le 120572119901 (1199090 1199091) 119901 (119909
0 1199092) + 119901 (119909
1 1199092) 119901 (119909
1 1199091)
119901 (1199090 1199092) + 119901 (119909
1 1199091)
+ 120573119901 (1199090 1199091) + (120572 + 120573)
le 120572 119901 (1199090 1199091) + 119901 (119909
1 1199092) + 120573119901 (119909
0 1199091) + (120572 + 120573)
(60)
because 119901(1199090 1199092) lt 119901(119909
0 1199092) + 119901(119909
1 1199091) and 119901(119909
1 1199091) lt
119901(1199091 1199091) + 119901(119909
0 1199092) Thus we get
119901 (1199091 1199092) le (
120572 + 120573
1 minus 120572)119901 (119909
0 1199091) + (
120572 + 120573
1 minus 120572) (61)
It further implies that
119901 (1199091 1199092) le 119897119901 (119909
0 1199091) + 119897 (62)
By Lemma 8 we can choose 1199093isin 119878(1199092) such that
119901 (1199092 1199093)
le 119867119901(119879 (1199091) 119878 (119909
2)) +
(120572 + 120573)2
1 minus 120572
le 120572119901 (1199091 1198791199091) 119901 (119909
1 1198781199092) + 119901 (119909
2 1198781199092) 119901 (119909
2 1198791199091)
119901 (1199091 1198781199092) + 119901 (119909
2 1198791199091)
+ 120573119901 (1199091 1199092) +
(120572 + 120573)2
1 minus 120572
le 120572119901 (1199091 1199092) 119901 (119909
1 1199093) + 119901 (119909
2 1199093) 119901 (119909
2 1199092)
119901 (1199091 1199093) + 119901 (119909
2 1199092)
+ 120573119901 (1199091 1199092) +
(120572 + 120573)2
1 minus 120572
le 120572 119901 (1199091 1199092) + 119901 (119909
2 1199093) + 120573119901 (119909
1 1199092) +
(120572 + 120573)2
1 minus 120572
(63)
because 119901(1199091 1199093) lt 119901(119909
1 1199093) + 119901(119909
2 1199092) and 119901(119909
2 1199092) lt
119901(1199092 1199092) + 119901(119909
1 1199093) Thus we get
119901 (1199092 1199093) le (
120572 + 120573
1 minus 120572)119901 (119909
1 1199092) + (
120572 + 120573
1 minus 120572)
2
(64)
It further implies that
119901 (1199092 1199093) le 1198972119901 (1199090 1199090) + 21198972 (65)
Continuing in this manner one can obtain a sequence 119909119899 in
119883 as 1199092119899+1
isin 119878(1199092119899) and 119909
2119899+2isin 119879(119909
2119899+1) such that
119901 (119909119899 119909119899+1
) le 119897119901 (119909119899minus1
119909119899) + 119897 le sdot sdot sdot le 119897
119899119901 (1199090 1199091) + 119899119897119899
(66)
where 119897 = ((120572 + 120573)(1 minus 120572)) lt 1 for all 119899 ge 0 Withoutloss of generality assume that 119898 gt 119899 Then using (66) andthe triangle inequality for partial metrics (P
4) one can easily
prove that
119901 (119909119899 119909119898) le
119898minus1
sum
119894=119899
119897119894119901 (1199090 1199091) +
119898minus1
sum
119894=119899
119894119897119894
997888rarr 0 as 119899 997888rarr +infin (since 0 lt 119897 lt 1)
(67)
By the definition of 119901119904
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (68)
This yields that 119909119899 is a Cauchy sequence in (119883 119901
119904) Since
(119883 119901) is complete then from Lemma 2(4) (119883 119901119904) is a com-
plete metric space Therefore the sequence 119909119899 converges
to some 1199091015840
isin 119883 with respect to the metric 119901119904 that is
lim119899rarr+infin
119901119904(119909119899 1199091015840) = 0 Again from Lemma 2(4) we get
119901 (1199091015840 1199091015840) = lim119899rarr+infin
119901 (119909119899 119909) = lim119899rarr+infin
119901 (119909119899 119909119899) = 0
(69)
Abstract and Applied Analysis 9
119867119901(119879 (1199092119899+1
) 119878 (1199091015840))
le 120572 (119901 (1199092119899+1
119879 (1199092119899+1
)) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 119879 (1199092119899+1
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 119879 (1199092119899+1
)))minus1
+ 120573119901 (1199092119899+1
119909)
le 120572 (119901 ((1199092119899+1
1199092119899+2
) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 1199092119899+2
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 1199092119899+2
))minus1
+ 120573119901 (1199092119899+1
119909)
(70)
therefore
lim119899rarr+infin
119867119901(119879 (1199092119899+1
) 119878 (1199091015840)) = 0 (71)
Now 1199092119899+2
isin 119879(1199092119899+1
) gives that
119901 (1199092119899+2
119878 (1199091015840)) le 119867
119901(119879 (1199092119899+1
) 119878 (1199091015840)) (72)
which implies that
lim119899rarr+infin
119901 (1199092119899+2
119878 (1199091015840)) = 0 (73)
On the other hand we have
119901 (1199091015840 119878 (1199091015840)) le 119901 (119909
1015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (1199091015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
(74)
Taking limit as 119899 rarr +infin and using (69) and (73) we obtain119901(1199091015840 119878(1199091015840)) = 0 Therefore from (69) (119901(1199091015840 1199091015840) = 0) we
obtain
119901 (1199091015840 119878 (1199091015840)) = 119901 (119909
1015840 1199091015840) (75)
which from Remark 14 implies that 1199091015840
isin 119878(1199091015840) = 119878(1199091015840)
It follows similarly that 1199091015840
isin 119879(1199091015840) Thus 119878 and 119879 have a
common fixed point
Now we give an example which illustrates our Theo-rem 26
Example 27 Let 119883 = 1 2 3 be endowed with usual orderand let 119901 be a partial metric on119883 defined as
119901 (1 1) = 119901 (2 2) = 0 119901 (3 3) =5
11
119901 (1 2) = 119901 (2 1) =3
10
119901 (1 3) = 119901 (3 1) =9
20
119901 (2 3) = 119901 (3 2) =1
2
(76)
Define the mappings 119878 119879 119883 rarr 119862119861119901(119883) by
119878119909 = 1 if 119909 119910 isin 1 2
1 2 otherwise
119879119909 = 1 if 119909 119910 isin 1 2
2 otherwise
(77)
Note that 119878119909 and 119879119909 are closed and bounded for all 119909 isin 119883
with respect to the partial metric 119901 To show that for all 119909 119910in119883 (59) is satisfied with 120572 = 111 120573 = 45 we consider thefollowing cases if 119909 119910 isin 1 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 1) = 0 (78)
and condition (59) is satisfied obviously
If 119909 = 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 2) =
3
10
119901 (119909 119878119909) = 119901 (119910 119878119909) = 119901 (3 1 2) =9
20
119901 (119909 119879119910) = 119901 (119910 119879119910) = 119901 (119910 119878119909) = 119901 (3 2) =11
24
119901 (119909 119910) = 119901 (3 3) =5
11
(79)
If 119909 = 3 119910 = 1 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (1 1) = 0 119901 (119910 119878119909) = 119901 (1 1 2) = 0
119901 (119909 119910) = 119901 (3 1) =9
20
(80)
10 Abstract and Applied Analysis
If 119909 = 3 119910 = 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (2 1) =3
10 119901 (119910 119878119909) = 119901 (2 1 2) = 0
119901 (119909 119910) = 119901 (3 2) =1
2
(81)
If 119909 = 1 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (1 1) = 0 119901 (119909 119879119910) = 119901 (1 2) =3
10
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (1 3) =9
20
(82)
If 119909 = 2 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (2 1) =3
10 119901 (119909 119879119910) = 119901 (2 2) = 0
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (2 3) =1
2
(83)
Thus all the conditions ofTheorem 26 are satisfied Here 119909 =
1 is a common fixed point of 119878 and 119879On the other hand the metric 119901
119904 induced by the partialmetric 119901 is given by
119901119904(1 1) = 119901
119904(2 2) = 119901
119904(3 3) = 0
119901119904(2 1) = 119901
119904(2 1) =
3
4
119901119904(3 2) = 119901
119904(2 3) =
4
7
119901119904(3 1) = 119901
119904(1 3) =
14
29
(84)
Note that in case of ordinary Hausdorff metric given map-ping does not satisfy the condition Indeed for 119909 = 1 and119910 = 3 we have
119867(119878119909 119879119910) = 119867 (1 2) =3
4
119901119904(119909 119878119909) = 119901
119904(1 1) = 0
119901119904(119909 119879119910) = 119901
119904(1 2) =
3
4
119901119904(119910 119879119910) = 119901
119904(3 2) =
4
7
119901119904(119910 119878119909) = 119901
119904(3 1) =
14
29
(85)
for the values of 120572 = 111 120573 = 45 By a routine calculationone can easily verify that the mapping does not satisfy thecondition which involved ordinary Hausdorff metric
Acknowledgment
This paper was funded by the Deanship of Scientific Research(DSR) King Abdulaziz University Jeddah The authorstherefore acknowledge with thanks DSR technical and finan-cial support
References
[1] S G Matthews ldquoPartial metric topologyrdquo in Proceedings of the8th Summer Conference on General Topology and Applicationsvol 728 pp 183ndash197 New York Academy of Science 1994
[2] T Abdeljawad E Karapinar andK Tas ldquoA generalized contrac-tion principle with control functions on partial metric spacesrdquoComputers amp Mathematics with Applications vol 63 no 3 pp716ndash719 2012
[3] T Abdeljawad ldquoFixed points for generalized weakly contractivemappings in partialmetric spacesrdquoMathematical andComputerModelling vol 54 no 11-12 pp 2923ndash2927 2011
[4] J Ahmad M Arshad and C Vetro ldquoOn a theorem of Khan in ageneralized metric spacerdquo International Journal of Analysis vol2013 Article ID 852727 6 pages 2013
[5] S Alsulami N Hussain and A Alotaibi ldquoCoupled fixed andcoincidence points for monotone operators in partial metricspacesrdquo Fixed Point Theory and Applications vol 2012 article173 2012
[6] I Altun and A Erduran ldquoFixed point theorems for monotonemappings on partial metric spacesrdquo Fixed Point Theory andApplications vol 2011 Article ID 508730 2011
[7] M Arshad J Ahmad and E Karapinar ldquoSome common fixedpoint results in rectangularmetric spacesrdquo International Journalof Analysis vol 2013 Article ID 307234 7 pages 2013
[8] M Arshad E Karapinar and J Ahmad ldquoSome unique fixedpoint theorem for rational contractions in partially orderedmetric spacesrdquo Journal of Inequalities andApplications vol 2013article 248 2013
[9] H Aydi M Abbas and C Vetro ldquoPartial Hausdorff metric andNadlerrsquos fixed point theorem on partial metric spacesrdquo Topologyand Its Applications vol 159 no 14 pp 3234ndash3242 2012
Abstract and Applied Analysis 11
[10] H Aydi M Abbas and C Vetro ldquoCommon Fixed points formultivalued generalized contractions on partial metric spacesrdquoRevista de la Real Academia de Ciencias Exactas Fisicas yNaturales A 2013
[11] A Azam and M Arshad ldquoFixed points of a sequence of locallycontractive multivalued mapsrdquo Computers amp Mathematics withApplications vol 57 no 1 pp 96ndash100 2009
[12] A Azam B Fisher and M Khan ldquoCommon fixed point the-orems in complex valued metric spacesrdquo Numerical FunctionalAnalysis and Optimization vol 32 no 3 pp 243ndash253 2011
[13] S Banach ldquoSur les operations dans les ensembles abstraitset leurs applications aux equations integralesrdquo FundamentaMathematicae vol 3 pp 133ndash181 1922
[14] I Beg and A Azam ldquoFixed points of asymptotically regularmultivalued mappingsrdquo Journal of the Australian MathematicalSociety A vol 53 no 3 pp 313ndash326 1992
[15] V W Bryant ldquoA remark on a fixed-point theorem for iteratedmappingsrdquo The American Mathematical Monthly vol 75 pp399ndash400 1968
[16] K P Chi E Karapınar and T D Thanh ldquoA generalizedcontraction principle in partial metric spacesrdquo Mathematicaland Computer Modelling vol 55 no 5-6 pp 1673ndash1681 2012
[17] N Hussain H K Nashine Z Kadelburg and S M AlsulamildquoWeakly isotone increasingmappings and endpoints in partiallyordered metric spacesrdquo Journal of Inequalities and Applicationsvol 2012 article 232 2012
[18] NHussain DDJoric Z Kadelburg and S Radenovic ldquoSuzuki-type fixed point results in metric type spacesrdquo Fixed PointTheory and Applications vol 2012 article 126 2012
[19] N Hussain Z Kadelburg S Radenovic and F R Al-SolamyldquoComparison functions and fixed point results in partial metricspacesrdquo Abstract and Applied Analysis vol 2012 Article ID605781 15 pages 2012
[20] N Hussain and M Abbas ldquoCommon fixed point results fortwo new classes of hybrid pairs in symmetric spacesrdquo AppliedMathematics and Computation vol 218 no 2 pp 542ndash547 2011
[21] S Hong ldquoFixed points of multivalued operators in orderedmetric spaces with applicationsrdquo Nonlinear Analysis TheoryMethods amp Applications vol 72 no 11 pp 3929ndash3942 2010
[22] S Hong ldquoFixed points for mixed monotone multivalued oper-ators in Banach spaces with applicationsrdquo Journal of Mathemat-ical Analysis and Applications vol 337 no 1 pp 333ndash342 2008
[23] S Hong ldquoFixed points of discontinuous multivalued increasingoperators in Banach spaces with applicationsrdquo Journal of Math-ematical Analysis and Applications vol 282 no 1 pp 151ndash1622003
[24] M Imdad J Ali and M Tanveer ldquoCoincidence and commonfixed point theorems for nonlinear contractions in Menger PMspacesrdquo Chaos Solitons amp Fractals vol 42 no 5 pp 3121ndash31292009
[25] E Karapinar ldquoCiric type nonunique fixed point theorems onpartial metric spacesrdquo The Journal of Nonlinear Science andApplications vol 5 no 2 pp 74ndash83 2012
[26] E Karapnar and I M Erhan ldquoFixed point theorems for opera-tors on partial metric spacesrdquo Applied Mathematics Letters vol24 no 11 pp 1894ndash1899 2011
[27] E KarapinarMMarudai andV Pragadeeshwarar ldquoFixed pointtheorems for generalized weak contractions satisfying rationalexpressions on ordered Partial Metric Spacerdquo LobachevskiiJournal of Mathematics vol 34 no 1 pp 116ndash123 2013
[28] M S Khan M Swaleh and M Imdad Some Fixed PointTheorems IV Communications 1983
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Differential EquationsInternational Journal of
Volume 2014
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Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Decision SciencesAdvances in
Discrete MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom
Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
Abstract and Applied Analysis 7
le 120572119901 (1199091 1199092) + 120573
119901 (1199091 1199092) 119901 (119909
2 1199093)
1 + 119901 (1199091 1199092)
+ 120574119901 (1199091 1199092) 119901 (119909
1 1199093)
1 + 119901 (1199091 1199092)
+(120572 + 120574)
2
1 minus 120573 minus 120574
le 120572119901 (1199091 1199092) + 120573119901 (119909
2 1199093) + 120574119901 (119909
1 1199093)
+(120572 + 120574)
2
1 minus 120573 minus 120574
(46)
So we get
119901 (1199092 1199093) le (
120572 + 120574
1 minus 120573 minus 120574)
2
119901 (1199090 1199091) + 2(
120572 + 120574
1 minus 120573 minus 120574)
2
(47)
Continuing in this manner one can obtain a sequence 119909119899 in
119883 as 1199092119899+1
isin 119878(1199092119899) and 119909
2119899+2isin 119879(119909
2119899+1) such that
119901 (119909119899 119909119899+1
) le 119872119901 (119909119899minus1
119909119899) + 119872
le sdot sdot sdot le 119872119899119901 (1199090 1199091) + 119899119872
119899
(48)
where 119872 = ((120572 + 120573)(1 minus 120572)) lt 1 for all 119899 ge 0 Without lossof generality assume that 119899 gt 119898 Then using (48) and thetriangle inequality for partial metrics (P
4) we have
119901 (119909119899 119909119898)
le 119901 (119909119899 119909119899+1
) + 119901 (119909119899+1
119909119899+2
) + sdot sdot sdot + 119901 (119909119898minus1
119909119898)
le 119872119899119901 (1199090 1199091) + 119899119872
119899+ 119872119899+1
119901 (1199090 1199091)
+ (119899 + 1)119872119899+1
+ sdot sdot sdot + 119872119898minus1
119901 (1199090 1199091)
+ (119898 minus 1)119872119898minus1
le
119898minus1
sum
119894=119899
119872119894119901 (1199090 1199091)
+
119898minus1
sum
119894=119899
119894119872119894997888rarr 0 as 119899 997888rarr +infin (since 0 lt 119872 lt 1)
(49)
By the definition of 119901119904 we get
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (50)
This yields that 119909119899 is a Cauchy sequence in (119883 119901
119904) Since
(119883 119901) is complete then from Lemma 2(4) (119883 119901119904) is a com-
plete metric space Therefore the sequence 119909119899 converges
to some 119909lowast
isin 119883 with respect to the metric 119901119904 that is
lim119899rarr+infin
119901119904(119909119899 119909lowast) = 0 Again from Lemma 2(4) we get
119901 (119909lowast 119909lowast) = lim119899rarr+infin
119901 (119909119899 119909lowast) = lim119899rarr+infin
119901 (119909119899 119909119899) = 0 (51)
119867119901(119879 (1199092119899+2
) 119878 (119909lowast))
le 120572119901 (1199092119899+2
119909lowast)
+ 120573119901 (1199092119899+2
119879 (1199092119899+2
)) 119901 (119909lowast 119878 (119909lowast))
1 + 119901 (1199092119899+2
119909lowast)
+ 120574119901 (1199092119899+2
119878 (119909lowast)) 119901 (119909
lowast 119879 (1199092119899+2
))
1 + 119901 (1199092119899+2
119909lowast)
le 120572119901 (1199092119899+2
119909lowast)
+ 120573119901 (1199092119899+2
1199092119899+3
) 119901 (119909lowast 119878 (119909lowast))
1 + 119901 (1199092119899+2
119909lowast)
+ 120574119901 (1199092119899+2
119878 (119909lowast)) 119901 (119909
lowast 1199092119899+1
)
1 + 119901 (1199092119899+2
119909lowast)
(52)
taking limit as 119899 rarr infin and using (51) we get
lim119899rarr+infin
119867119901(119879 (1199092119899+2
) 119878 (119909lowast)) = 0 (53)
Now 1199092119899+1
isin 119879(1199092119899+2
) gives that
119901 (1199092119899+1
119878 (119909lowast)) le 119867
119901(119879 (1199092119899+2
) 119878 (119909lowast)) (54)
which implies that
lim119899rarr+infin
119901 (1199092119899+1
119878 (119909lowast)) = 0 (55)
On the other hand by (P4) we have
119901 (119909lowast 119878 (119909lowast)) le 119901 (119909
lowast 1199092119899+2
) + 119901 (1199092119899+2
119878 (119909lowast))
minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (119909lowast 1199092119899+2
) + 119901 (1199092119899+2
119878 (119909lowast))
(56)
Taking limit as 119899 rarr +infin and using (51) and (55) we obtain119901(119909lowast 119878(119909lowast)) = 0 Therefore from (51) (119901(119909lowast 119909lowast) = 0) we
obtain
119901 (119909lowast 119878 (119909lowast)) = 119901 (119909
lowast 119909lowast) (57)
which from Remark 14 implies that 119909lowast
isin 119878(119909lowast) = 119878(119909lowast)
Similarly one can easily prove that 119909lowast isin 119879(119909lowast) Thus 119878 and
119879 have a common fixed point
Remark 24 For 120573 = 120574 = 0 and 119878 = 119879 Theorem 23 reduces tothe following result of Aydi et al [9]
Corollary 25 (see [9 Theorem 32]) Let (119883 119901) be a partialmetric space If 119879 119883 rarr 119862119861
119901(119883) is a multivalued mapping
such that for all 119909 119910 isin 119883 one has
119867119901(119879119909 119879119910) le 119896119901 (119886 119887) (58)
where 119896 isin (0 1) Then 119879 has a fixed point
8 Abstract and Applied Analysis
Theorem26 Let (119883 119901) be a complete partialmetric space and119878 119879 119883 rarr 119862119861
119901(119883) be multivalued mappings such that
119867119901(119878119909 119879119910) le 120572
119901 (119909 119878119909) 119901 (119909 119879119910) + 119901 (119910 119879119910) 119901 (119910 119878119909)
119901 (119909 119879119910) + 119901 (119910 119878119909)
+ 120573119889 (119909 119910)
(59)
for all 119909 119910 isin 119883 0 le 120572 120573 with 2120572 + 120573 lt 1 and 119901(119909 119879119910) +
119901(119910 119878119909) = 0 Then 119878 and 119879 have a common fixed point
Proof Assume that 119897 = (120572+120573)(1minus120572) Let 1199090isin 119883 be arbitrary
but fixed element of119883 and choose 1199091isin 119878(1199090)
When 119901(119909 119879119910)+119901(119910 119878119909) = 0 By Lemma 8we can choose1199092isin 119879(119909
1) such that
119901 (1199091 1199092)
le 119867119901(119878 (1199090) 119879 (119909
1)) + (120572 + 120573)
le 120572119901 (1199090 1198781199090) 119901 (119909
0 1198791199091) + 119901 (119909
1 1198791199091) 119901 (119909
1 1198781199090)
119901 (1199090 1198791199091) + 119901 (119909
1 1198781199090)
+ 120573119901 (1199090 1199091) + (120572 + 120573)
le 120572119901 (1199090 1199091) 119901 (119909
0 1199092) + 119901 (119909
1 1199092) 119901 (119909
1 1199091)
119901 (1199090 1199092) + 119901 (119909
1 1199091)
+ 120573119901 (1199090 1199091) + (120572 + 120573)
le 120572 119901 (1199090 1199091) + 119901 (119909
1 1199092) + 120573119901 (119909
0 1199091) + (120572 + 120573)
(60)
because 119901(1199090 1199092) lt 119901(119909
0 1199092) + 119901(119909
1 1199091) and 119901(119909
1 1199091) lt
119901(1199091 1199091) + 119901(119909
0 1199092) Thus we get
119901 (1199091 1199092) le (
120572 + 120573
1 minus 120572)119901 (119909
0 1199091) + (
120572 + 120573
1 minus 120572) (61)
It further implies that
119901 (1199091 1199092) le 119897119901 (119909
0 1199091) + 119897 (62)
By Lemma 8 we can choose 1199093isin 119878(1199092) such that
119901 (1199092 1199093)
le 119867119901(119879 (1199091) 119878 (119909
2)) +
(120572 + 120573)2
1 minus 120572
le 120572119901 (1199091 1198791199091) 119901 (119909
1 1198781199092) + 119901 (119909
2 1198781199092) 119901 (119909
2 1198791199091)
119901 (1199091 1198781199092) + 119901 (119909
2 1198791199091)
+ 120573119901 (1199091 1199092) +
(120572 + 120573)2
1 minus 120572
le 120572119901 (1199091 1199092) 119901 (119909
1 1199093) + 119901 (119909
2 1199093) 119901 (119909
2 1199092)
119901 (1199091 1199093) + 119901 (119909
2 1199092)
+ 120573119901 (1199091 1199092) +
(120572 + 120573)2
1 minus 120572
le 120572 119901 (1199091 1199092) + 119901 (119909
2 1199093) + 120573119901 (119909
1 1199092) +
(120572 + 120573)2
1 minus 120572
(63)
because 119901(1199091 1199093) lt 119901(119909
1 1199093) + 119901(119909
2 1199092) and 119901(119909
2 1199092) lt
119901(1199092 1199092) + 119901(119909
1 1199093) Thus we get
119901 (1199092 1199093) le (
120572 + 120573
1 minus 120572)119901 (119909
1 1199092) + (
120572 + 120573
1 minus 120572)
2
(64)
It further implies that
119901 (1199092 1199093) le 1198972119901 (1199090 1199090) + 21198972 (65)
Continuing in this manner one can obtain a sequence 119909119899 in
119883 as 1199092119899+1
isin 119878(1199092119899) and 119909
2119899+2isin 119879(119909
2119899+1) such that
119901 (119909119899 119909119899+1
) le 119897119901 (119909119899minus1
119909119899) + 119897 le sdot sdot sdot le 119897
119899119901 (1199090 1199091) + 119899119897119899
(66)
where 119897 = ((120572 + 120573)(1 minus 120572)) lt 1 for all 119899 ge 0 Withoutloss of generality assume that 119898 gt 119899 Then using (66) andthe triangle inequality for partial metrics (P
4) one can easily
prove that
119901 (119909119899 119909119898) le
119898minus1
sum
119894=119899
119897119894119901 (1199090 1199091) +
119898minus1
sum
119894=119899
119894119897119894
997888rarr 0 as 119899 997888rarr +infin (since 0 lt 119897 lt 1)
(67)
By the definition of 119901119904
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (68)
This yields that 119909119899 is a Cauchy sequence in (119883 119901
119904) Since
(119883 119901) is complete then from Lemma 2(4) (119883 119901119904) is a com-
plete metric space Therefore the sequence 119909119899 converges
to some 1199091015840
isin 119883 with respect to the metric 119901119904 that is
lim119899rarr+infin
119901119904(119909119899 1199091015840) = 0 Again from Lemma 2(4) we get
119901 (1199091015840 1199091015840) = lim119899rarr+infin
119901 (119909119899 119909) = lim119899rarr+infin
119901 (119909119899 119909119899) = 0
(69)
Abstract and Applied Analysis 9
119867119901(119879 (1199092119899+1
) 119878 (1199091015840))
le 120572 (119901 (1199092119899+1
119879 (1199092119899+1
)) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 119879 (1199092119899+1
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 119879 (1199092119899+1
)))minus1
+ 120573119901 (1199092119899+1
119909)
le 120572 (119901 ((1199092119899+1
1199092119899+2
) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 1199092119899+2
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 1199092119899+2
))minus1
+ 120573119901 (1199092119899+1
119909)
(70)
therefore
lim119899rarr+infin
119867119901(119879 (1199092119899+1
) 119878 (1199091015840)) = 0 (71)
Now 1199092119899+2
isin 119879(1199092119899+1
) gives that
119901 (1199092119899+2
119878 (1199091015840)) le 119867
119901(119879 (1199092119899+1
) 119878 (1199091015840)) (72)
which implies that
lim119899rarr+infin
119901 (1199092119899+2
119878 (1199091015840)) = 0 (73)
On the other hand we have
119901 (1199091015840 119878 (1199091015840)) le 119901 (119909
1015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (1199091015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
(74)
Taking limit as 119899 rarr +infin and using (69) and (73) we obtain119901(1199091015840 119878(1199091015840)) = 0 Therefore from (69) (119901(1199091015840 1199091015840) = 0) we
obtain
119901 (1199091015840 119878 (1199091015840)) = 119901 (119909
1015840 1199091015840) (75)
which from Remark 14 implies that 1199091015840
isin 119878(1199091015840) = 119878(1199091015840)
It follows similarly that 1199091015840
isin 119879(1199091015840) Thus 119878 and 119879 have a
common fixed point
Now we give an example which illustrates our Theo-rem 26
Example 27 Let 119883 = 1 2 3 be endowed with usual orderand let 119901 be a partial metric on119883 defined as
119901 (1 1) = 119901 (2 2) = 0 119901 (3 3) =5
11
119901 (1 2) = 119901 (2 1) =3
10
119901 (1 3) = 119901 (3 1) =9
20
119901 (2 3) = 119901 (3 2) =1
2
(76)
Define the mappings 119878 119879 119883 rarr 119862119861119901(119883) by
119878119909 = 1 if 119909 119910 isin 1 2
1 2 otherwise
119879119909 = 1 if 119909 119910 isin 1 2
2 otherwise
(77)
Note that 119878119909 and 119879119909 are closed and bounded for all 119909 isin 119883
with respect to the partial metric 119901 To show that for all 119909 119910in119883 (59) is satisfied with 120572 = 111 120573 = 45 we consider thefollowing cases if 119909 119910 isin 1 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 1) = 0 (78)
and condition (59) is satisfied obviously
If 119909 = 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 2) =
3
10
119901 (119909 119878119909) = 119901 (119910 119878119909) = 119901 (3 1 2) =9
20
119901 (119909 119879119910) = 119901 (119910 119879119910) = 119901 (119910 119878119909) = 119901 (3 2) =11
24
119901 (119909 119910) = 119901 (3 3) =5
11
(79)
If 119909 = 3 119910 = 1 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (1 1) = 0 119901 (119910 119878119909) = 119901 (1 1 2) = 0
119901 (119909 119910) = 119901 (3 1) =9
20
(80)
10 Abstract and Applied Analysis
If 119909 = 3 119910 = 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (2 1) =3
10 119901 (119910 119878119909) = 119901 (2 1 2) = 0
119901 (119909 119910) = 119901 (3 2) =1
2
(81)
If 119909 = 1 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (1 1) = 0 119901 (119909 119879119910) = 119901 (1 2) =3
10
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (1 3) =9
20
(82)
If 119909 = 2 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (2 1) =3
10 119901 (119909 119879119910) = 119901 (2 2) = 0
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (2 3) =1
2
(83)
Thus all the conditions ofTheorem 26 are satisfied Here 119909 =
1 is a common fixed point of 119878 and 119879On the other hand the metric 119901
119904 induced by the partialmetric 119901 is given by
119901119904(1 1) = 119901
119904(2 2) = 119901
119904(3 3) = 0
119901119904(2 1) = 119901
119904(2 1) =
3
4
119901119904(3 2) = 119901
119904(2 3) =
4
7
119901119904(3 1) = 119901
119904(1 3) =
14
29
(84)
Note that in case of ordinary Hausdorff metric given map-ping does not satisfy the condition Indeed for 119909 = 1 and119910 = 3 we have
119867(119878119909 119879119910) = 119867 (1 2) =3
4
119901119904(119909 119878119909) = 119901
119904(1 1) = 0
119901119904(119909 119879119910) = 119901
119904(1 2) =
3
4
119901119904(119910 119879119910) = 119901
119904(3 2) =
4
7
119901119904(119910 119878119909) = 119901
119904(3 1) =
14
29
(85)
for the values of 120572 = 111 120573 = 45 By a routine calculationone can easily verify that the mapping does not satisfy thecondition which involved ordinary Hausdorff metric
Acknowledgment
This paper was funded by the Deanship of Scientific Research(DSR) King Abdulaziz University Jeddah The authorstherefore acknowledge with thanks DSR technical and finan-cial support
References
[1] S G Matthews ldquoPartial metric topologyrdquo in Proceedings of the8th Summer Conference on General Topology and Applicationsvol 728 pp 183ndash197 New York Academy of Science 1994
[2] T Abdeljawad E Karapinar andK Tas ldquoA generalized contrac-tion principle with control functions on partial metric spacesrdquoComputers amp Mathematics with Applications vol 63 no 3 pp716ndash719 2012
[3] T Abdeljawad ldquoFixed points for generalized weakly contractivemappings in partialmetric spacesrdquoMathematical andComputerModelling vol 54 no 11-12 pp 2923ndash2927 2011
[4] J Ahmad M Arshad and C Vetro ldquoOn a theorem of Khan in ageneralized metric spacerdquo International Journal of Analysis vol2013 Article ID 852727 6 pages 2013
[5] S Alsulami N Hussain and A Alotaibi ldquoCoupled fixed andcoincidence points for monotone operators in partial metricspacesrdquo Fixed Point Theory and Applications vol 2012 article173 2012
[6] I Altun and A Erduran ldquoFixed point theorems for monotonemappings on partial metric spacesrdquo Fixed Point Theory andApplications vol 2011 Article ID 508730 2011
[7] M Arshad J Ahmad and E Karapinar ldquoSome common fixedpoint results in rectangularmetric spacesrdquo International Journalof Analysis vol 2013 Article ID 307234 7 pages 2013
[8] M Arshad E Karapinar and J Ahmad ldquoSome unique fixedpoint theorem for rational contractions in partially orderedmetric spacesrdquo Journal of Inequalities andApplications vol 2013article 248 2013
[9] H Aydi M Abbas and C Vetro ldquoPartial Hausdorff metric andNadlerrsquos fixed point theorem on partial metric spacesrdquo Topologyand Its Applications vol 159 no 14 pp 3234ndash3242 2012
Abstract and Applied Analysis 11
[10] H Aydi M Abbas and C Vetro ldquoCommon Fixed points formultivalued generalized contractions on partial metric spacesrdquoRevista de la Real Academia de Ciencias Exactas Fisicas yNaturales A 2013
[11] A Azam and M Arshad ldquoFixed points of a sequence of locallycontractive multivalued mapsrdquo Computers amp Mathematics withApplications vol 57 no 1 pp 96ndash100 2009
[12] A Azam B Fisher and M Khan ldquoCommon fixed point the-orems in complex valued metric spacesrdquo Numerical FunctionalAnalysis and Optimization vol 32 no 3 pp 243ndash253 2011
[13] S Banach ldquoSur les operations dans les ensembles abstraitset leurs applications aux equations integralesrdquo FundamentaMathematicae vol 3 pp 133ndash181 1922
[14] I Beg and A Azam ldquoFixed points of asymptotically regularmultivalued mappingsrdquo Journal of the Australian MathematicalSociety A vol 53 no 3 pp 313ndash326 1992
[15] V W Bryant ldquoA remark on a fixed-point theorem for iteratedmappingsrdquo The American Mathematical Monthly vol 75 pp399ndash400 1968
[16] K P Chi E Karapınar and T D Thanh ldquoA generalizedcontraction principle in partial metric spacesrdquo Mathematicaland Computer Modelling vol 55 no 5-6 pp 1673ndash1681 2012
[17] N Hussain H K Nashine Z Kadelburg and S M AlsulamildquoWeakly isotone increasingmappings and endpoints in partiallyordered metric spacesrdquo Journal of Inequalities and Applicationsvol 2012 article 232 2012
[18] NHussain DDJoric Z Kadelburg and S Radenovic ldquoSuzuki-type fixed point results in metric type spacesrdquo Fixed PointTheory and Applications vol 2012 article 126 2012
[19] N Hussain Z Kadelburg S Radenovic and F R Al-SolamyldquoComparison functions and fixed point results in partial metricspacesrdquo Abstract and Applied Analysis vol 2012 Article ID605781 15 pages 2012
[20] N Hussain and M Abbas ldquoCommon fixed point results fortwo new classes of hybrid pairs in symmetric spacesrdquo AppliedMathematics and Computation vol 218 no 2 pp 542ndash547 2011
[21] S Hong ldquoFixed points of multivalued operators in orderedmetric spaces with applicationsrdquo Nonlinear Analysis TheoryMethods amp Applications vol 72 no 11 pp 3929ndash3942 2010
[22] S Hong ldquoFixed points for mixed monotone multivalued oper-ators in Banach spaces with applicationsrdquo Journal of Mathemat-ical Analysis and Applications vol 337 no 1 pp 333ndash342 2008
[23] S Hong ldquoFixed points of discontinuous multivalued increasingoperators in Banach spaces with applicationsrdquo Journal of Math-ematical Analysis and Applications vol 282 no 1 pp 151ndash1622003
[24] M Imdad J Ali and M Tanveer ldquoCoincidence and commonfixed point theorems for nonlinear contractions in Menger PMspacesrdquo Chaos Solitons amp Fractals vol 42 no 5 pp 3121ndash31292009
[25] E Karapinar ldquoCiric type nonunique fixed point theorems onpartial metric spacesrdquo The Journal of Nonlinear Science andApplications vol 5 no 2 pp 74ndash83 2012
[26] E Karapnar and I M Erhan ldquoFixed point theorems for opera-tors on partial metric spacesrdquo Applied Mathematics Letters vol24 no 11 pp 1894ndash1899 2011
[27] E KarapinarMMarudai andV Pragadeeshwarar ldquoFixed pointtheorems for generalized weak contractions satisfying rationalexpressions on ordered Partial Metric Spacerdquo LobachevskiiJournal of Mathematics vol 34 no 1 pp 116ndash123 2013
[28] M S Khan M Swaleh and M Imdad Some Fixed PointTheorems IV Communications 1983
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Differential EquationsInternational Journal of
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Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
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Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
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Decision SciencesAdvances in
Discrete MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom
Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
8 Abstract and Applied Analysis
Theorem26 Let (119883 119901) be a complete partialmetric space and119878 119879 119883 rarr 119862119861
119901(119883) be multivalued mappings such that
119867119901(119878119909 119879119910) le 120572
119901 (119909 119878119909) 119901 (119909 119879119910) + 119901 (119910 119879119910) 119901 (119910 119878119909)
119901 (119909 119879119910) + 119901 (119910 119878119909)
+ 120573119889 (119909 119910)
(59)
for all 119909 119910 isin 119883 0 le 120572 120573 with 2120572 + 120573 lt 1 and 119901(119909 119879119910) +
119901(119910 119878119909) = 0 Then 119878 and 119879 have a common fixed point
Proof Assume that 119897 = (120572+120573)(1minus120572) Let 1199090isin 119883 be arbitrary
but fixed element of119883 and choose 1199091isin 119878(1199090)
When 119901(119909 119879119910)+119901(119910 119878119909) = 0 By Lemma 8we can choose1199092isin 119879(119909
1) such that
119901 (1199091 1199092)
le 119867119901(119878 (1199090) 119879 (119909
1)) + (120572 + 120573)
le 120572119901 (1199090 1198781199090) 119901 (119909
0 1198791199091) + 119901 (119909
1 1198791199091) 119901 (119909
1 1198781199090)
119901 (1199090 1198791199091) + 119901 (119909
1 1198781199090)
+ 120573119901 (1199090 1199091) + (120572 + 120573)
le 120572119901 (1199090 1199091) 119901 (119909
0 1199092) + 119901 (119909
1 1199092) 119901 (119909
1 1199091)
119901 (1199090 1199092) + 119901 (119909
1 1199091)
+ 120573119901 (1199090 1199091) + (120572 + 120573)
le 120572 119901 (1199090 1199091) + 119901 (119909
1 1199092) + 120573119901 (119909
0 1199091) + (120572 + 120573)
(60)
because 119901(1199090 1199092) lt 119901(119909
0 1199092) + 119901(119909
1 1199091) and 119901(119909
1 1199091) lt
119901(1199091 1199091) + 119901(119909
0 1199092) Thus we get
119901 (1199091 1199092) le (
120572 + 120573
1 minus 120572)119901 (119909
0 1199091) + (
120572 + 120573
1 minus 120572) (61)
It further implies that
119901 (1199091 1199092) le 119897119901 (119909
0 1199091) + 119897 (62)
By Lemma 8 we can choose 1199093isin 119878(1199092) such that
119901 (1199092 1199093)
le 119867119901(119879 (1199091) 119878 (119909
2)) +
(120572 + 120573)2
1 minus 120572
le 120572119901 (1199091 1198791199091) 119901 (119909
1 1198781199092) + 119901 (119909
2 1198781199092) 119901 (119909
2 1198791199091)
119901 (1199091 1198781199092) + 119901 (119909
2 1198791199091)
+ 120573119901 (1199091 1199092) +
(120572 + 120573)2
1 minus 120572
le 120572119901 (1199091 1199092) 119901 (119909
1 1199093) + 119901 (119909
2 1199093) 119901 (119909
2 1199092)
119901 (1199091 1199093) + 119901 (119909
2 1199092)
+ 120573119901 (1199091 1199092) +
(120572 + 120573)2
1 minus 120572
le 120572 119901 (1199091 1199092) + 119901 (119909
2 1199093) + 120573119901 (119909
1 1199092) +
(120572 + 120573)2
1 minus 120572
(63)
because 119901(1199091 1199093) lt 119901(119909
1 1199093) + 119901(119909
2 1199092) and 119901(119909
2 1199092) lt
119901(1199092 1199092) + 119901(119909
1 1199093) Thus we get
119901 (1199092 1199093) le (
120572 + 120573
1 minus 120572)119901 (119909
1 1199092) + (
120572 + 120573
1 minus 120572)
2
(64)
It further implies that
119901 (1199092 1199093) le 1198972119901 (1199090 1199090) + 21198972 (65)
Continuing in this manner one can obtain a sequence 119909119899 in
119883 as 1199092119899+1
isin 119878(1199092119899) and 119909
2119899+2isin 119879(119909
2119899+1) such that
119901 (119909119899 119909119899+1
) le 119897119901 (119909119899minus1
119909119899) + 119897 le sdot sdot sdot le 119897
119899119901 (1199090 1199091) + 119899119897119899
(66)
where 119897 = ((120572 + 120573)(1 minus 120572)) lt 1 for all 119899 ge 0 Withoutloss of generality assume that 119898 gt 119899 Then using (66) andthe triangle inequality for partial metrics (P
4) one can easily
prove that
119901 (119909119899 119909119898) le
119898minus1
sum
119894=119899
119897119894119901 (1199090 1199091) +
119898minus1
sum
119894=119899
119894119897119894
997888rarr 0 as 119899 997888rarr +infin (since 0 lt 119897 lt 1)
(67)
By the definition of 119901119904
119901119904(119909119899 119909119898) le 2119901 (119909
119899 119909119898) 997888rarr 0 as 119899 997888rarr +infin (68)
This yields that 119909119899 is a Cauchy sequence in (119883 119901
119904) Since
(119883 119901) is complete then from Lemma 2(4) (119883 119901119904) is a com-
plete metric space Therefore the sequence 119909119899 converges
to some 1199091015840
isin 119883 with respect to the metric 119901119904 that is
lim119899rarr+infin
119901119904(119909119899 1199091015840) = 0 Again from Lemma 2(4) we get
119901 (1199091015840 1199091015840) = lim119899rarr+infin
119901 (119909119899 119909) = lim119899rarr+infin
119901 (119909119899 119909119899) = 0
(69)
Abstract and Applied Analysis 9
119867119901(119879 (1199092119899+1
) 119878 (1199091015840))
le 120572 (119901 (1199092119899+1
119879 (1199092119899+1
)) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 119879 (1199092119899+1
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 119879 (1199092119899+1
)))minus1
+ 120573119901 (1199092119899+1
119909)
le 120572 (119901 ((1199092119899+1
1199092119899+2
) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 1199092119899+2
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 1199092119899+2
))minus1
+ 120573119901 (1199092119899+1
119909)
(70)
therefore
lim119899rarr+infin
119867119901(119879 (1199092119899+1
) 119878 (1199091015840)) = 0 (71)
Now 1199092119899+2
isin 119879(1199092119899+1
) gives that
119901 (1199092119899+2
119878 (1199091015840)) le 119867
119901(119879 (1199092119899+1
) 119878 (1199091015840)) (72)
which implies that
lim119899rarr+infin
119901 (1199092119899+2
119878 (1199091015840)) = 0 (73)
On the other hand we have
119901 (1199091015840 119878 (1199091015840)) le 119901 (119909
1015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (1199091015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
(74)
Taking limit as 119899 rarr +infin and using (69) and (73) we obtain119901(1199091015840 119878(1199091015840)) = 0 Therefore from (69) (119901(1199091015840 1199091015840) = 0) we
obtain
119901 (1199091015840 119878 (1199091015840)) = 119901 (119909
1015840 1199091015840) (75)
which from Remark 14 implies that 1199091015840
isin 119878(1199091015840) = 119878(1199091015840)
It follows similarly that 1199091015840
isin 119879(1199091015840) Thus 119878 and 119879 have a
common fixed point
Now we give an example which illustrates our Theo-rem 26
Example 27 Let 119883 = 1 2 3 be endowed with usual orderand let 119901 be a partial metric on119883 defined as
119901 (1 1) = 119901 (2 2) = 0 119901 (3 3) =5
11
119901 (1 2) = 119901 (2 1) =3
10
119901 (1 3) = 119901 (3 1) =9
20
119901 (2 3) = 119901 (3 2) =1
2
(76)
Define the mappings 119878 119879 119883 rarr 119862119861119901(119883) by
119878119909 = 1 if 119909 119910 isin 1 2
1 2 otherwise
119879119909 = 1 if 119909 119910 isin 1 2
2 otherwise
(77)
Note that 119878119909 and 119879119909 are closed and bounded for all 119909 isin 119883
with respect to the partial metric 119901 To show that for all 119909 119910in119883 (59) is satisfied with 120572 = 111 120573 = 45 we consider thefollowing cases if 119909 119910 isin 1 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 1) = 0 (78)
and condition (59) is satisfied obviously
If 119909 = 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 2) =
3
10
119901 (119909 119878119909) = 119901 (119910 119878119909) = 119901 (3 1 2) =9
20
119901 (119909 119879119910) = 119901 (119910 119879119910) = 119901 (119910 119878119909) = 119901 (3 2) =11
24
119901 (119909 119910) = 119901 (3 3) =5
11
(79)
If 119909 = 3 119910 = 1 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (1 1) = 0 119901 (119910 119878119909) = 119901 (1 1 2) = 0
119901 (119909 119910) = 119901 (3 1) =9
20
(80)
10 Abstract and Applied Analysis
If 119909 = 3 119910 = 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (2 1) =3
10 119901 (119910 119878119909) = 119901 (2 1 2) = 0
119901 (119909 119910) = 119901 (3 2) =1
2
(81)
If 119909 = 1 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (1 1) = 0 119901 (119909 119879119910) = 119901 (1 2) =3
10
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (1 3) =9
20
(82)
If 119909 = 2 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (2 1) =3
10 119901 (119909 119879119910) = 119901 (2 2) = 0
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (2 3) =1
2
(83)
Thus all the conditions ofTheorem 26 are satisfied Here 119909 =
1 is a common fixed point of 119878 and 119879On the other hand the metric 119901
119904 induced by the partialmetric 119901 is given by
119901119904(1 1) = 119901
119904(2 2) = 119901
119904(3 3) = 0
119901119904(2 1) = 119901
119904(2 1) =
3
4
119901119904(3 2) = 119901
119904(2 3) =
4
7
119901119904(3 1) = 119901
119904(1 3) =
14
29
(84)
Note that in case of ordinary Hausdorff metric given map-ping does not satisfy the condition Indeed for 119909 = 1 and119910 = 3 we have
119867(119878119909 119879119910) = 119867 (1 2) =3
4
119901119904(119909 119878119909) = 119901
119904(1 1) = 0
119901119904(119909 119879119910) = 119901
119904(1 2) =
3
4
119901119904(119910 119879119910) = 119901
119904(3 2) =
4
7
119901119904(119910 119878119909) = 119901
119904(3 1) =
14
29
(85)
for the values of 120572 = 111 120573 = 45 By a routine calculationone can easily verify that the mapping does not satisfy thecondition which involved ordinary Hausdorff metric
Acknowledgment
This paper was funded by the Deanship of Scientific Research(DSR) King Abdulaziz University Jeddah The authorstherefore acknowledge with thanks DSR technical and finan-cial support
References
[1] S G Matthews ldquoPartial metric topologyrdquo in Proceedings of the8th Summer Conference on General Topology and Applicationsvol 728 pp 183ndash197 New York Academy of Science 1994
[2] T Abdeljawad E Karapinar andK Tas ldquoA generalized contrac-tion principle with control functions on partial metric spacesrdquoComputers amp Mathematics with Applications vol 63 no 3 pp716ndash719 2012
[3] T Abdeljawad ldquoFixed points for generalized weakly contractivemappings in partialmetric spacesrdquoMathematical andComputerModelling vol 54 no 11-12 pp 2923ndash2927 2011
[4] J Ahmad M Arshad and C Vetro ldquoOn a theorem of Khan in ageneralized metric spacerdquo International Journal of Analysis vol2013 Article ID 852727 6 pages 2013
[5] S Alsulami N Hussain and A Alotaibi ldquoCoupled fixed andcoincidence points for monotone operators in partial metricspacesrdquo Fixed Point Theory and Applications vol 2012 article173 2012
[6] I Altun and A Erduran ldquoFixed point theorems for monotonemappings on partial metric spacesrdquo Fixed Point Theory andApplications vol 2011 Article ID 508730 2011
[7] M Arshad J Ahmad and E Karapinar ldquoSome common fixedpoint results in rectangularmetric spacesrdquo International Journalof Analysis vol 2013 Article ID 307234 7 pages 2013
[8] M Arshad E Karapinar and J Ahmad ldquoSome unique fixedpoint theorem for rational contractions in partially orderedmetric spacesrdquo Journal of Inequalities andApplications vol 2013article 248 2013
[9] H Aydi M Abbas and C Vetro ldquoPartial Hausdorff metric andNadlerrsquos fixed point theorem on partial metric spacesrdquo Topologyand Its Applications vol 159 no 14 pp 3234ndash3242 2012
Abstract and Applied Analysis 11
[10] H Aydi M Abbas and C Vetro ldquoCommon Fixed points formultivalued generalized contractions on partial metric spacesrdquoRevista de la Real Academia de Ciencias Exactas Fisicas yNaturales A 2013
[11] A Azam and M Arshad ldquoFixed points of a sequence of locallycontractive multivalued mapsrdquo Computers amp Mathematics withApplications vol 57 no 1 pp 96ndash100 2009
[12] A Azam B Fisher and M Khan ldquoCommon fixed point the-orems in complex valued metric spacesrdquo Numerical FunctionalAnalysis and Optimization vol 32 no 3 pp 243ndash253 2011
[13] S Banach ldquoSur les operations dans les ensembles abstraitset leurs applications aux equations integralesrdquo FundamentaMathematicae vol 3 pp 133ndash181 1922
[14] I Beg and A Azam ldquoFixed points of asymptotically regularmultivalued mappingsrdquo Journal of the Australian MathematicalSociety A vol 53 no 3 pp 313ndash326 1992
[15] V W Bryant ldquoA remark on a fixed-point theorem for iteratedmappingsrdquo The American Mathematical Monthly vol 75 pp399ndash400 1968
[16] K P Chi E Karapınar and T D Thanh ldquoA generalizedcontraction principle in partial metric spacesrdquo Mathematicaland Computer Modelling vol 55 no 5-6 pp 1673ndash1681 2012
[17] N Hussain H K Nashine Z Kadelburg and S M AlsulamildquoWeakly isotone increasingmappings and endpoints in partiallyordered metric spacesrdquo Journal of Inequalities and Applicationsvol 2012 article 232 2012
[18] NHussain DDJoric Z Kadelburg and S Radenovic ldquoSuzuki-type fixed point results in metric type spacesrdquo Fixed PointTheory and Applications vol 2012 article 126 2012
[19] N Hussain Z Kadelburg S Radenovic and F R Al-SolamyldquoComparison functions and fixed point results in partial metricspacesrdquo Abstract and Applied Analysis vol 2012 Article ID605781 15 pages 2012
[20] N Hussain and M Abbas ldquoCommon fixed point results fortwo new classes of hybrid pairs in symmetric spacesrdquo AppliedMathematics and Computation vol 218 no 2 pp 542ndash547 2011
[21] S Hong ldquoFixed points of multivalued operators in orderedmetric spaces with applicationsrdquo Nonlinear Analysis TheoryMethods amp Applications vol 72 no 11 pp 3929ndash3942 2010
[22] S Hong ldquoFixed points for mixed monotone multivalued oper-ators in Banach spaces with applicationsrdquo Journal of Mathemat-ical Analysis and Applications vol 337 no 1 pp 333ndash342 2008
[23] S Hong ldquoFixed points of discontinuous multivalued increasingoperators in Banach spaces with applicationsrdquo Journal of Math-ematical Analysis and Applications vol 282 no 1 pp 151ndash1622003
[24] M Imdad J Ali and M Tanveer ldquoCoincidence and commonfixed point theorems for nonlinear contractions in Menger PMspacesrdquo Chaos Solitons amp Fractals vol 42 no 5 pp 3121ndash31292009
[25] E Karapinar ldquoCiric type nonunique fixed point theorems onpartial metric spacesrdquo The Journal of Nonlinear Science andApplications vol 5 no 2 pp 74ndash83 2012
[26] E Karapnar and I M Erhan ldquoFixed point theorems for opera-tors on partial metric spacesrdquo Applied Mathematics Letters vol24 no 11 pp 1894ndash1899 2011
[27] E KarapinarMMarudai andV Pragadeeshwarar ldquoFixed pointtheorems for generalized weak contractions satisfying rationalexpressions on ordered Partial Metric Spacerdquo LobachevskiiJournal of Mathematics vol 34 no 1 pp 116ndash123 2013
[28] M S Khan M Swaleh and M Imdad Some Fixed PointTheorems IV Communications 1983
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical Problems in Engineering
Hindawi Publishing Corporationhttpwwwhindawicom
Differential EquationsInternational Journal of
Volume 2014
Applied MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical PhysicsAdvances in
Complex AnalysisJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
OptimizationJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Operations ResearchAdvances in
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Decision SciencesAdvances in
Discrete MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom
Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
Abstract and Applied Analysis 9
119867119901(119879 (1199092119899+1
) 119878 (1199091015840))
le 120572 (119901 (1199092119899+1
119879 (1199092119899+1
)) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 119879 (1199092119899+1
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 119879 (1199092119899+1
)))minus1
+ 120573119901 (1199092119899+1
119909)
le 120572 (119901 ((1199092119899+1
1199092119899+2
) 119901 (1199092119899+1
119878 (1199091015840))
+119901 (1199091015840 119878 (1199091015840)) 119901 (119909
1015840 1199092119899+2
)))
times(119901 (1199092119899+1
119878 (1199091015840)) + 119901 (119909
1015840 1199092119899+2
))minus1
+ 120573119901 (1199092119899+1
119909)
(70)
therefore
lim119899rarr+infin
119867119901(119879 (1199092119899+1
) 119878 (1199091015840)) = 0 (71)
Now 1199092119899+2
isin 119879(1199092119899+1
) gives that
119901 (1199092119899+2
119878 (1199091015840)) le 119867
119901(119879 (1199092119899+1
) 119878 (1199091015840)) (72)
which implies that
lim119899rarr+infin
119901 (1199092119899+2
119878 (1199091015840)) = 0 (73)
On the other hand we have
119901 (1199091015840 119878 (1199091015840)) le 119901 (119909
1015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
minus 119901 (1199092119899+2
1199092119899+2
)
le 119901 (1199091015840 1199092119899+2
) + 119901 (1199092119899+2
119878 (1199091015840))
(74)
Taking limit as 119899 rarr +infin and using (69) and (73) we obtain119901(1199091015840 119878(1199091015840)) = 0 Therefore from (69) (119901(1199091015840 1199091015840) = 0) we
obtain
119901 (1199091015840 119878 (1199091015840)) = 119901 (119909
1015840 1199091015840) (75)
which from Remark 14 implies that 1199091015840
isin 119878(1199091015840) = 119878(1199091015840)
It follows similarly that 1199091015840
isin 119879(1199091015840) Thus 119878 and 119879 have a
common fixed point
Now we give an example which illustrates our Theo-rem 26
Example 27 Let 119883 = 1 2 3 be endowed with usual orderand let 119901 be a partial metric on119883 defined as
119901 (1 1) = 119901 (2 2) = 0 119901 (3 3) =5
11
119901 (1 2) = 119901 (2 1) =3
10
119901 (1 3) = 119901 (3 1) =9
20
119901 (2 3) = 119901 (3 2) =1
2
(76)
Define the mappings 119878 119879 119883 rarr 119862119861119901(119883) by
119878119909 = 1 if 119909 119910 isin 1 2
1 2 otherwise
119879119909 = 1 if 119909 119910 isin 1 2
2 otherwise
(77)
Note that 119878119909 and 119879119909 are closed and bounded for all 119909 isin 119883
with respect to the partial metric 119901 To show that for all 119909 119910in119883 (59) is satisfied with 120572 = 111 120573 = 45 we consider thefollowing cases if 119909 119910 isin 1 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 1) = 0 (78)
and condition (59) is satisfied obviously
If 119909 = 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 2) =
3
10
119901 (119909 119878119909) = 119901 (119910 119878119909) = 119901 (3 1 2) =9
20
119901 (119909 119879119910) = 119901 (119910 119879119910) = 119901 (119910 119878119909) = 119901 (3 2) =11
24
119901 (119909 119910) = 119901 (3 3) =5
11
(79)
If 119909 = 3 119910 = 1 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (1 1) = 0 119901 (119910 119878119909) = 119901 (1 1 2) = 0
119901 (119909 119910) = 119901 (3 1) =9
20
(80)
10 Abstract and Applied Analysis
If 119909 = 3 119910 = 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (2 1) =3
10 119901 (119910 119878119909) = 119901 (2 1 2) = 0
119901 (119909 119910) = 119901 (3 2) =1
2
(81)
If 119909 = 1 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (1 1) = 0 119901 (119909 119879119910) = 119901 (1 2) =3
10
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (1 3) =9
20
(82)
If 119909 = 2 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (2 1) =3
10 119901 (119909 119879119910) = 119901 (2 2) = 0
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (2 3) =1
2
(83)
Thus all the conditions ofTheorem 26 are satisfied Here 119909 =
1 is a common fixed point of 119878 and 119879On the other hand the metric 119901
119904 induced by the partialmetric 119901 is given by
119901119904(1 1) = 119901
119904(2 2) = 119901
119904(3 3) = 0
119901119904(2 1) = 119901
119904(2 1) =
3
4
119901119904(3 2) = 119901
119904(2 3) =
4
7
119901119904(3 1) = 119901
119904(1 3) =
14
29
(84)
Note that in case of ordinary Hausdorff metric given map-ping does not satisfy the condition Indeed for 119909 = 1 and119910 = 3 we have
119867(119878119909 119879119910) = 119867 (1 2) =3
4
119901119904(119909 119878119909) = 119901
119904(1 1) = 0
119901119904(119909 119879119910) = 119901
119904(1 2) =
3
4
119901119904(119910 119879119910) = 119901
119904(3 2) =
4
7
119901119904(119910 119878119909) = 119901
119904(3 1) =
14
29
(85)
for the values of 120572 = 111 120573 = 45 By a routine calculationone can easily verify that the mapping does not satisfy thecondition which involved ordinary Hausdorff metric
Acknowledgment
This paper was funded by the Deanship of Scientific Research(DSR) King Abdulaziz University Jeddah The authorstherefore acknowledge with thanks DSR technical and finan-cial support
References
[1] S G Matthews ldquoPartial metric topologyrdquo in Proceedings of the8th Summer Conference on General Topology and Applicationsvol 728 pp 183ndash197 New York Academy of Science 1994
[2] T Abdeljawad E Karapinar andK Tas ldquoA generalized contrac-tion principle with control functions on partial metric spacesrdquoComputers amp Mathematics with Applications vol 63 no 3 pp716ndash719 2012
[3] T Abdeljawad ldquoFixed points for generalized weakly contractivemappings in partialmetric spacesrdquoMathematical andComputerModelling vol 54 no 11-12 pp 2923ndash2927 2011
[4] J Ahmad M Arshad and C Vetro ldquoOn a theorem of Khan in ageneralized metric spacerdquo International Journal of Analysis vol2013 Article ID 852727 6 pages 2013
[5] S Alsulami N Hussain and A Alotaibi ldquoCoupled fixed andcoincidence points for monotone operators in partial metricspacesrdquo Fixed Point Theory and Applications vol 2012 article173 2012
[6] I Altun and A Erduran ldquoFixed point theorems for monotonemappings on partial metric spacesrdquo Fixed Point Theory andApplications vol 2011 Article ID 508730 2011
[7] M Arshad J Ahmad and E Karapinar ldquoSome common fixedpoint results in rectangularmetric spacesrdquo International Journalof Analysis vol 2013 Article ID 307234 7 pages 2013
[8] M Arshad E Karapinar and J Ahmad ldquoSome unique fixedpoint theorem for rational contractions in partially orderedmetric spacesrdquo Journal of Inequalities andApplications vol 2013article 248 2013
[9] H Aydi M Abbas and C Vetro ldquoPartial Hausdorff metric andNadlerrsquos fixed point theorem on partial metric spacesrdquo Topologyand Its Applications vol 159 no 14 pp 3234ndash3242 2012
Abstract and Applied Analysis 11
[10] H Aydi M Abbas and C Vetro ldquoCommon Fixed points formultivalued generalized contractions on partial metric spacesrdquoRevista de la Real Academia de Ciencias Exactas Fisicas yNaturales A 2013
[11] A Azam and M Arshad ldquoFixed points of a sequence of locallycontractive multivalued mapsrdquo Computers amp Mathematics withApplications vol 57 no 1 pp 96ndash100 2009
[12] A Azam B Fisher and M Khan ldquoCommon fixed point the-orems in complex valued metric spacesrdquo Numerical FunctionalAnalysis and Optimization vol 32 no 3 pp 243ndash253 2011
[13] S Banach ldquoSur les operations dans les ensembles abstraitset leurs applications aux equations integralesrdquo FundamentaMathematicae vol 3 pp 133ndash181 1922
[14] I Beg and A Azam ldquoFixed points of asymptotically regularmultivalued mappingsrdquo Journal of the Australian MathematicalSociety A vol 53 no 3 pp 313ndash326 1992
[15] V W Bryant ldquoA remark on a fixed-point theorem for iteratedmappingsrdquo The American Mathematical Monthly vol 75 pp399ndash400 1968
[16] K P Chi E Karapınar and T D Thanh ldquoA generalizedcontraction principle in partial metric spacesrdquo Mathematicaland Computer Modelling vol 55 no 5-6 pp 1673ndash1681 2012
[17] N Hussain H K Nashine Z Kadelburg and S M AlsulamildquoWeakly isotone increasingmappings and endpoints in partiallyordered metric spacesrdquo Journal of Inequalities and Applicationsvol 2012 article 232 2012
[18] NHussain DDJoric Z Kadelburg and S Radenovic ldquoSuzuki-type fixed point results in metric type spacesrdquo Fixed PointTheory and Applications vol 2012 article 126 2012
[19] N Hussain Z Kadelburg S Radenovic and F R Al-SolamyldquoComparison functions and fixed point results in partial metricspacesrdquo Abstract and Applied Analysis vol 2012 Article ID605781 15 pages 2012
[20] N Hussain and M Abbas ldquoCommon fixed point results fortwo new classes of hybrid pairs in symmetric spacesrdquo AppliedMathematics and Computation vol 218 no 2 pp 542ndash547 2011
[21] S Hong ldquoFixed points of multivalued operators in orderedmetric spaces with applicationsrdquo Nonlinear Analysis TheoryMethods amp Applications vol 72 no 11 pp 3929ndash3942 2010
[22] S Hong ldquoFixed points for mixed monotone multivalued oper-ators in Banach spaces with applicationsrdquo Journal of Mathemat-ical Analysis and Applications vol 337 no 1 pp 333ndash342 2008
[23] S Hong ldquoFixed points of discontinuous multivalued increasingoperators in Banach spaces with applicationsrdquo Journal of Math-ematical Analysis and Applications vol 282 no 1 pp 151ndash1622003
[24] M Imdad J Ali and M Tanveer ldquoCoincidence and commonfixed point theorems for nonlinear contractions in Menger PMspacesrdquo Chaos Solitons amp Fractals vol 42 no 5 pp 3121ndash31292009
[25] E Karapinar ldquoCiric type nonunique fixed point theorems onpartial metric spacesrdquo The Journal of Nonlinear Science andApplications vol 5 no 2 pp 74ndash83 2012
[26] E Karapnar and I M Erhan ldquoFixed point theorems for opera-tors on partial metric spacesrdquo Applied Mathematics Letters vol24 no 11 pp 1894ndash1899 2011
[27] E KarapinarMMarudai andV Pragadeeshwarar ldquoFixed pointtheorems for generalized weak contractions satisfying rationalexpressions on ordered Partial Metric Spacerdquo LobachevskiiJournal of Mathematics vol 34 no 1 pp 116ndash123 2013
[28] M S Khan M Swaleh and M Imdad Some Fixed PointTheorems IV Communications 1983
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical Problems in Engineering
Hindawi Publishing Corporationhttpwwwhindawicom
Differential EquationsInternational Journal of
Volume 2014
Applied MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical PhysicsAdvances in
Complex AnalysisJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
OptimizationJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Operations ResearchAdvances in
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Decision SciencesAdvances in
Discrete MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom
Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
10 Abstract and Applied Analysis
If 119909 = 3 119910 = 2 then
119867119901(119878119909 119879119910) = 119867
119901(1 2 1) =
3
10
119901 (119909 119878119909)=119901 (3 1 2)=9
20 119901 (119909 119879119910)=119901 (3 1)=
9
20
119901 (119910 119879119910) = 119901 (2 1) =3
10 119901 (119910 119878119909) = 119901 (2 1 2) = 0
119901 (119909 119910) = 119901 (3 2) =1
2
(81)
If 119909 = 1 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (1 1) = 0 119901 (119909 119879119910) = 119901 (1 2) =3
10
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (1 3) =9
20
(82)
If 119909 = 2 119910 = 3 then
119867119901(119878119909 119879119910) = 119867
119901(1 2) =
3
10
119901 (119909 119878119909) = 119901 (2 1) =3
10 119901 (119909 119879119910) = 119901 (2 2) = 0
119901 (119910 119879119910) = 119901 (3 2) =1
2 119901 (119910 119878119909) = 119901 (3 1) =
9
20
119901 (119909 119910) = 119901 (2 3) =1
2
(83)
Thus all the conditions ofTheorem 26 are satisfied Here 119909 =
1 is a common fixed point of 119878 and 119879On the other hand the metric 119901
119904 induced by the partialmetric 119901 is given by
119901119904(1 1) = 119901
119904(2 2) = 119901
119904(3 3) = 0
119901119904(2 1) = 119901
119904(2 1) =
3
4
119901119904(3 2) = 119901
119904(2 3) =
4
7
119901119904(3 1) = 119901
119904(1 3) =
14
29
(84)
Note that in case of ordinary Hausdorff metric given map-ping does not satisfy the condition Indeed for 119909 = 1 and119910 = 3 we have
119867(119878119909 119879119910) = 119867 (1 2) =3
4
119901119904(119909 119878119909) = 119901
119904(1 1) = 0
119901119904(119909 119879119910) = 119901
119904(1 2) =
3
4
119901119904(119910 119879119910) = 119901
119904(3 2) =
4
7
119901119904(119910 119878119909) = 119901
119904(3 1) =
14
29
(85)
for the values of 120572 = 111 120573 = 45 By a routine calculationone can easily verify that the mapping does not satisfy thecondition which involved ordinary Hausdorff metric
Acknowledgment
This paper was funded by the Deanship of Scientific Research(DSR) King Abdulaziz University Jeddah The authorstherefore acknowledge with thanks DSR technical and finan-cial support
References
[1] S G Matthews ldquoPartial metric topologyrdquo in Proceedings of the8th Summer Conference on General Topology and Applicationsvol 728 pp 183ndash197 New York Academy of Science 1994
[2] T Abdeljawad E Karapinar andK Tas ldquoA generalized contrac-tion principle with control functions on partial metric spacesrdquoComputers amp Mathematics with Applications vol 63 no 3 pp716ndash719 2012
[3] T Abdeljawad ldquoFixed points for generalized weakly contractivemappings in partialmetric spacesrdquoMathematical andComputerModelling vol 54 no 11-12 pp 2923ndash2927 2011
[4] J Ahmad M Arshad and C Vetro ldquoOn a theorem of Khan in ageneralized metric spacerdquo International Journal of Analysis vol2013 Article ID 852727 6 pages 2013
[5] S Alsulami N Hussain and A Alotaibi ldquoCoupled fixed andcoincidence points for monotone operators in partial metricspacesrdquo Fixed Point Theory and Applications vol 2012 article173 2012
[6] I Altun and A Erduran ldquoFixed point theorems for monotonemappings on partial metric spacesrdquo Fixed Point Theory andApplications vol 2011 Article ID 508730 2011
[7] M Arshad J Ahmad and E Karapinar ldquoSome common fixedpoint results in rectangularmetric spacesrdquo International Journalof Analysis vol 2013 Article ID 307234 7 pages 2013
[8] M Arshad E Karapinar and J Ahmad ldquoSome unique fixedpoint theorem for rational contractions in partially orderedmetric spacesrdquo Journal of Inequalities andApplications vol 2013article 248 2013
[9] H Aydi M Abbas and C Vetro ldquoPartial Hausdorff metric andNadlerrsquos fixed point theorem on partial metric spacesrdquo Topologyand Its Applications vol 159 no 14 pp 3234ndash3242 2012
Abstract and Applied Analysis 11
[10] H Aydi M Abbas and C Vetro ldquoCommon Fixed points formultivalued generalized contractions on partial metric spacesrdquoRevista de la Real Academia de Ciencias Exactas Fisicas yNaturales A 2013
[11] A Azam and M Arshad ldquoFixed points of a sequence of locallycontractive multivalued mapsrdquo Computers amp Mathematics withApplications vol 57 no 1 pp 96ndash100 2009
[12] A Azam B Fisher and M Khan ldquoCommon fixed point the-orems in complex valued metric spacesrdquo Numerical FunctionalAnalysis and Optimization vol 32 no 3 pp 243ndash253 2011
[13] S Banach ldquoSur les operations dans les ensembles abstraitset leurs applications aux equations integralesrdquo FundamentaMathematicae vol 3 pp 133ndash181 1922
[14] I Beg and A Azam ldquoFixed points of asymptotically regularmultivalued mappingsrdquo Journal of the Australian MathematicalSociety A vol 53 no 3 pp 313ndash326 1992
[15] V W Bryant ldquoA remark on a fixed-point theorem for iteratedmappingsrdquo The American Mathematical Monthly vol 75 pp399ndash400 1968
[16] K P Chi E Karapınar and T D Thanh ldquoA generalizedcontraction principle in partial metric spacesrdquo Mathematicaland Computer Modelling vol 55 no 5-6 pp 1673ndash1681 2012
[17] N Hussain H K Nashine Z Kadelburg and S M AlsulamildquoWeakly isotone increasingmappings and endpoints in partiallyordered metric spacesrdquo Journal of Inequalities and Applicationsvol 2012 article 232 2012
[18] NHussain DDJoric Z Kadelburg and S Radenovic ldquoSuzuki-type fixed point results in metric type spacesrdquo Fixed PointTheory and Applications vol 2012 article 126 2012
[19] N Hussain Z Kadelburg S Radenovic and F R Al-SolamyldquoComparison functions and fixed point results in partial metricspacesrdquo Abstract and Applied Analysis vol 2012 Article ID605781 15 pages 2012
[20] N Hussain and M Abbas ldquoCommon fixed point results fortwo new classes of hybrid pairs in symmetric spacesrdquo AppliedMathematics and Computation vol 218 no 2 pp 542ndash547 2011
[21] S Hong ldquoFixed points of multivalued operators in orderedmetric spaces with applicationsrdquo Nonlinear Analysis TheoryMethods amp Applications vol 72 no 11 pp 3929ndash3942 2010
[22] S Hong ldquoFixed points for mixed monotone multivalued oper-ators in Banach spaces with applicationsrdquo Journal of Mathemat-ical Analysis and Applications vol 337 no 1 pp 333ndash342 2008
[23] S Hong ldquoFixed points of discontinuous multivalued increasingoperators in Banach spaces with applicationsrdquo Journal of Math-ematical Analysis and Applications vol 282 no 1 pp 151ndash1622003
[24] M Imdad J Ali and M Tanveer ldquoCoincidence and commonfixed point theorems for nonlinear contractions in Menger PMspacesrdquo Chaos Solitons amp Fractals vol 42 no 5 pp 3121ndash31292009
[25] E Karapinar ldquoCiric type nonunique fixed point theorems onpartial metric spacesrdquo The Journal of Nonlinear Science andApplications vol 5 no 2 pp 74ndash83 2012
[26] E Karapnar and I M Erhan ldquoFixed point theorems for opera-tors on partial metric spacesrdquo Applied Mathematics Letters vol24 no 11 pp 1894ndash1899 2011
[27] E KarapinarMMarudai andV Pragadeeshwarar ldquoFixed pointtheorems for generalized weak contractions satisfying rationalexpressions on ordered Partial Metric Spacerdquo LobachevskiiJournal of Mathematics vol 34 no 1 pp 116ndash123 2013
[28] M S Khan M Swaleh and M Imdad Some Fixed PointTheorems IV Communications 1983
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical Problems in Engineering
Hindawi Publishing Corporationhttpwwwhindawicom
Differential EquationsInternational Journal of
Volume 2014
Applied MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical PhysicsAdvances in
Complex AnalysisJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
OptimizationJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Operations ResearchAdvances in
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Decision SciencesAdvances in
Discrete MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom
Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
Abstract and Applied Analysis 11
[10] H Aydi M Abbas and C Vetro ldquoCommon Fixed points formultivalued generalized contractions on partial metric spacesrdquoRevista de la Real Academia de Ciencias Exactas Fisicas yNaturales A 2013
[11] A Azam and M Arshad ldquoFixed points of a sequence of locallycontractive multivalued mapsrdquo Computers amp Mathematics withApplications vol 57 no 1 pp 96ndash100 2009
[12] A Azam B Fisher and M Khan ldquoCommon fixed point the-orems in complex valued metric spacesrdquo Numerical FunctionalAnalysis and Optimization vol 32 no 3 pp 243ndash253 2011
[13] S Banach ldquoSur les operations dans les ensembles abstraitset leurs applications aux equations integralesrdquo FundamentaMathematicae vol 3 pp 133ndash181 1922
[14] I Beg and A Azam ldquoFixed points of asymptotically regularmultivalued mappingsrdquo Journal of the Australian MathematicalSociety A vol 53 no 3 pp 313ndash326 1992
[15] V W Bryant ldquoA remark on a fixed-point theorem for iteratedmappingsrdquo The American Mathematical Monthly vol 75 pp399ndash400 1968
[16] K P Chi E Karapınar and T D Thanh ldquoA generalizedcontraction principle in partial metric spacesrdquo Mathematicaland Computer Modelling vol 55 no 5-6 pp 1673ndash1681 2012
[17] N Hussain H K Nashine Z Kadelburg and S M AlsulamildquoWeakly isotone increasingmappings and endpoints in partiallyordered metric spacesrdquo Journal of Inequalities and Applicationsvol 2012 article 232 2012
[18] NHussain DDJoric Z Kadelburg and S Radenovic ldquoSuzuki-type fixed point results in metric type spacesrdquo Fixed PointTheory and Applications vol 2012 article 126 2012
[19] N Hussain Z Kadelburg S Radenovic and F R Al-SolamyldquoComparison functions and fixed point results in partial metricspacesrdquo Abstract and Applied Analysis vol 2012 Article ID605781 15 pages 2012
[20] N Hussain and M Abbas ldquoCommon fixed point results fortwo new classes of hybrid pairs in symmetric spacesrdquo AppliedMathematics and Computation vol 218 no 2 pp 542ndash547 2011
[21] S Hong ldquoFixed points of multivalued operators in orderedmetric spaces with applicationsrdquo Nonlinear Analysis TheoryMethods amp Applications vol 72 no 11 pp 3929ndash3942 2010
[22] S Hong ldquoFixed points for mixed monotone multivalued oper-ators in Banach spaces with applicationsrdquo Journal of Mathemat-ical Analysis and Applications vol 337 no 1 pp 333ndash342 2008
[23] S Hong ldquoFixed points of discontinuous multivalued increasingoperators in Banach spaces with applicationsrdquo Journal of Math-ematical Analysis and Applications vol 282 no 1 pp 151ndash1622003
[24] M Imdad J Ali and M Tanveer ldquoCoincidence and commonfixed point theorems for nonlinear contractions in Menger PMspacesrdquo Chaos Solitons amp Fractals vol 42 no 5 pp 3121ndash31292009
[25] E Karapinar ldquoCiric type nonunique fixed point theorems onpartial metric spacesrdquo The Journal of Nonlinear Science andApplications vol 5 no 2 pp 74ndash83 2012
[26] E Karapnar and I M Erhan ldquoFixed point theorems for opera-tors on partial metric spacesrdquo Applied Mathematics Letters vol24 no 11 pp 1894ndash1899 2011
[27] E KarapinarMMarudai andV Pragadeeshwarar ldquoFixed pointtheorems for generalized weak contractions satisfying rationalexpressions on ordered Partial Metric Spacerdquo LobachevskiiJournal of Mathematics vol 34 no 1 pp 116ndash123 2013
[28] M S Khan M Swaleh and M Imdad Some Fixed PointTheorems IV Communications 1983
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical Problems in Engineering
Hindawi Publishing Corporationhttpwwwhindawicom
Differential EquationsInternational Journal of
Volume 2014
Applied MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical PhysicsAdvances in
Complex AnalysisJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
OptimizationJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Operations ResearchAdvances in
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Decision SciencesAdvances in
Discrete MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom
Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of
Submit your manuscripts athttpwwwhindawicom
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical Problems in Engineering
Hindawi Publishing Corporationhttpwwwhindawicom
Differential EquationsInternational Journal of
Volume 2014
Applied MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Probability and StatisticsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Mathematical PhysicsAdvances in
Complex AnalysisJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
OptimizationJournal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
CombinatoricsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Operations ResearchAdvances in
Journal of
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Function Spaces
Abstract and Applied AnalysisHindawi Publishing Corporationhttpwwwhindawicom Volume 2014
International Journal of Mathematics and Mathematical Sciences
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Algebra
Discrete Dynamics in Nature and Society
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Decision SciencesAdvances in
Discrete MathematicsJournal of
Hindawi Publishing Corporationhttpwwwhindawicom
Volume 2014 Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014
Stochastic AnalysisInternational Journal of