math1013 calculus i tutorial 11 anti derivatives, reimann...
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MATH1013 Calculus I
Tutorial 11 Anti-derivatives, Reimann Sum and Fundamental Theorem of Calculus
1) Antiderivatives
2) Table of Formulas for Indefinite integral
3) Reimann Sum
4) Special Sums
Let 𝒏 be a positive number
∑ 𝒄 = 𝒄 𝒏𝒏𝒌=𝟏 ∑ 𝒌 =
𝒏 (𝒏+𝟏)
𝟐
𝒏𝒌=𝟏
∑ 𝒌𝟐 =𝒏 (𝒏+𝟏)(𝟐𝒏+𝟏)
𝟔
𝒏𝒌=𝟏 ∑ 𝒌𝟑 =
𝒏𝟐 (𝒏+𝟏)𝟐
𝟒
𝒏𝒌=𝟏
5) Definite Integral
6) Properties of Integrals
(a) ∫ 𝒇(𝒙)𝒅𝒙 = − ∫ 𝒇(𝒙)𝒅𝒙𝒂
𝒃
𝒃
𝒂
(b) ∫ 𝒇(𝒙)𝒅𝒙 = 𝟎𝒂
𝒂
(c) ∫ 𝒇(𝒙)𝒅𝒙 = ∫ 𝒇(𝒙)𝒅𝒙𝒄
𝒂
𝒃
𝒂+ ∫ 𝒇(𝒙)𝒅𝒙
𝒃
𝒄
7) Fundamental Theorem of Calculus
Example 1 : Evaluate ∫ √𝟐𝒙 + 𝟏𝟒
𝟎𝒅𝒙 .
Example 2: Calculate ∫ 𝒍𝒏𝒙
𝒙
𝒆
𝟏𝒅𝒙 .
8) Integration of Symmetric Functions
Exercises :
1) Evaluate the following integrals :
(a) ∫(𝟑𝒙𝟓 − 𝟓𝒙𝟗)𝒅𝒙 (b) ∫ (𝟒√𝒙 −𝟒
√𝒙) 𝒅𝒙
(c) ∫ (𝟏
𝒙 √𝒙𝟐−𝟐𝟓) 𝒅𝒙 (d) ∫ (
𝟏𝟐𝒕𝟖−𝒕
𝒕𝟑 ) 𝒅𝒕
(e) ∫(𝒔𝒊𝒏𝟐𝒚 + 𝒄𝒐𝒔𝟑𝒚)𝒅𝒚 (f) ∫(𝒔𝒆𝒄𝟐𝜽 + 𝒔𝒆𝒄𝜽 𝒕𝒂𝒏𝜽)𝒅𝜽
(g) ∫(𝒔𝒆𝒄 𝟒𝜽 𝒕𝒂𝒏 𝟒𝜽)𝒅𝜽 (h) ∫ 𝒆𝒙+𝟐 𝒅𝒙
(i) ∫ √𝒙 (𝟐𝒙𝟔 − 𝟒√𝒙𝟑
)𝒅𝒙 (j) ∫𝟐+𝒙𝟐
𝟏+𝒙𝟐 𝒅𝒙
2) Given the following velocity functions of an object moving along a line, find the
position function with the given initial position. Then graph both the velocity and
position functions.
(a) 𝒗(𝒕) = 𝟔𝒕𝟐 + 𝟒𝒕 − 𝟏𝟎 ; 𝒔(𝟎) = 𝟎
(b) 𝒗(𝒕) = 𝟐 𝒄𝒐𝒔 𝒕 ; 𝒔(𝟎) = 𝟎
3) Evaluate 𝐥𝐢𝐦𝒏→∞ {𝟏
𝒏+𝟏 +
𝟏
𝒏+𝟐 + ⋯
𝟏
𝒏+𝒏 } .
4) Prove that 𝐥𝐢𝐦𝒏→∞𝟏
𝒏 {𝒔𝒊𝒏
𝒕
𝒏+ 𝒔𝒊𝒏
𝟐𝒕
𝒏+ ⋯ + 𝒔𝒊𝒏
(𝒏−𝟏) 𝒕
𝒏} =
𝟏− 𝒄𝒐𝒔 𝒕
𝒕
5) Evaluate the following limit by identifying the integral that it represents :
𝐥𝐢𝐦𝒏→∞
∑ [(𝟒𝒌
𝒏)
𝟖
+ 𝟏]
𝒏
𝒌=𝟏
(𝟒
𝒏)
6) Fundamental Theorem of Calculus:
(a) 𝒅
𝒅𝒙 ∫ 𝒔𝒊𝒏𝟐 𝒕
𝒙
𝟏𝒅𝒕 (b)
𝒅
𝒅𝒙 ∫ √𝒕𝟐 + 𝟏
𝟓
𝒙𝒅𝒕 (c)
𝒅
𝒅𝒙 ∫ 𝒄𝒐𝒔 𝒕𝟐𝒙𝟐
𝟎𝒅𝒕
(d) 𝒅
𝒅𝒙 ∫ √𝟏 + 𝒕𝟐𝒙
−𝒙𝒅𝒕 (e)
𝒅
𝒅𝒙 ∫ 𝒍𝒏 𝒕𝟐𝒆𝟐𝒙
𝒆𝒙 𝒅𝒕
(f) 𝒅
𝒅𝒙 ∫
𝒅𝒛
𝒛𝟐+𝟏
𝟏𝟎
𝒙𝟐 (g) 𝒅
𝒅𝒙 ∫ (𝒕𝟒 + 𝟔)
𝒄𝒐𝒔 𝒙
𝟏𝒅𝒕
7) Even and Odd Functions
(a) ∫ (𝒕𝒂𝒏 𝒙) 𝒅𝒙𝝅
𝟒−𝝅
𝟒
(b) ∫𝒙𝟑−𝟒𝒙
𝒙𝟐+𝟏 𝒅𝒙
𝟐
−𝟐
8) Integration by Substitutions
(a) ∫ 𝒙𝟑 (𝒙𝟒 + 𝟏𝟔)𝟔 𝒅𝒙 (b) ∫𝟐
𝒙 √𝟒𝒙𝟐−𝟏 𝒅𝒙 , 𝒙 > 𝟐 .
(c) ∫(𝒙 + 𝟏) √𝟑𝒙 + 𝟐 𝒅𝒙 (d) ∫ (𝒔𝒊𝒏 𝒙
𝒄𝒐𝒔𝟐 𝒙) 𝒅𝒙
𝝅
𝟒𝟎
(e) ∫ 𝒙𝟐 𝒆𝒙𝟑+𝟏 𝒅𝒙𝟐
−𝟏 (f) ∫ (
√𝒙+𝟏
𝟐√𝒙)
𝟒
𝒅𝒙
(g) ∫ (𝒔𝒊𝒏 𝟐𝒚
𝒔𝒊𝒏𝟐𝒚+𝟐) 𝒅𝒚
𝝅
𝟔𝟎
(Hint: 𝒔𝒊𝒏𝟐𝒚 = 𝟐 𝒔𝒊𝒏𝒚 𝒄𝒐𝒔𝒚)
(h) ∫𝒍𝒏 𝒙
𝒙
𝒆𝟐
𝟏 𝒅𝒙
(i) ∫𝒅𝒙
√𝟏+√𝟏+𝒙 (Hint: Begin with 𝒖 = √𝟏 + 𝒙 )
9) (Briggs Revision Ex.5.3 #11) Area functions
The graph of 𝒇 is shown in the figure. Let 𝑨(𝒙) = ∫ 𝒇(𝒕)𝒅𝒕𝒙
−𝟐 and 𝑭(𝒙) = ∫ 𝒇(𝒕)𝒅𝒕
𝒙
𝟒
be two area functions for 𝒇. Evaluate the following area functions.
(a) 𝑨(−𝟐) (b) 𝑭(𝟖) (c) 𝑨(𝟒) (d) 𝑭(𝟒) (e) 𝑨(𝟖)
10) (Briggs Revision Ex.5.3 #12) Area functions The
graph of 𝒇 is shown in the figure. Let be two area functions 𝑨(𝒙) =
∫ 𝒇(𝒕)𝒅𝒕𝒙
𝟎 and 𝑭(𝒙) = ∫ 𝒇(𝒕)𝒅𝒕
𝒙
𝟐 for 𝒇. Evaluate the following
area functions.
(a) 𝑨(𝟐) (b) 𝑭(𝟓) (c) 𝑨(𝟎) (d) 𝑭(𝟖) (e) 𝑨(𝟖)
(f) 𝑨(𝟓) (g) 𝑭(𝟐)
Q11-12 Definite integrals (Briggs Ex.5.3 #23-24) Evaluate the
following integrals using the Fundamental Theorem of Calculus. Discuss whether your result is
consistent with the figure.
11) ∫ (𝒙𝟐 − 𝟐𝒙 + 𝟑) 𝒅𝒙𝟏
𝟎 12) ∫ (𝒔𝒊𝒏 𝒙 + 𝒄𝒐𝒔 𝒙) 𝒅𝒙
𝟕𝝅
𝟒−𝝅
𝟒
For Q13-18 (Briggs Revision Ex.5 #8-11) Limit definition of the definite
integral Use the limit definition of the definite integral with right Riemann sums and
a regular partition
∫ 𝐟(𝐱) 𝐝𝐱𝐛
𝐚= 𝐥𝐢𝐦
𝐧→∞ ∑ [𝐟(𝐱𝐤
∗)]𝐧𝐤=𝟏 (∆𝐱)
to evaluate the following definite integrals. Use the Fundamental Theorem of Calculus to check your answer.
13) ∫ (𝟒𝒙 − 𝟐) 𝒅𝒙𝟏
𝟎 14) ∫ (𝒙𝟐 − 𝟒) 𝒅𝒙
𝟐
𝟎
15) ∫ (𝟑𝒙𝟐 + 𝒙) 𝒅𝒙𝟐
𝟏 16) ∫ (𝒙𝟑 − 𝒙) 𝒅𝒙
𝟒
𝟎
(Briggs Revision Ex.5 #15-30)
Evaluating integrals Evaluate the following integrals.
17) ∫ (𝟑𝒙𝟒 − 𝟐𝒙 + 𝟏) 𝒅𝒙𝟐
−𝟐 18) ∫ 𝒄𝒐𝒔 𝟑𝒙 𝒅𝒙
19) ∫ (𝒙 + 𝟏) 𝟑𝒅𝒙𝟐
𝟎 20) ∫ (𝟒𝒙𝟐𝟏 − 𝟐𝒙𝟏𝟔 + 𝟏) 𝒅𝒙
𝟏
𝟎
21) ∫ (𝟗𝒙𝟖 − 𝟕𝒙𝟔) 𝒅𝒙𝟏
𝟎 22) ∫ (𝒆𝟒𝒙+𝟖) 𝒅𝒙
𝟐
−𝟐
23) ∫ √𝒙 (√𝒙 + 𝟏) 𝒅𝒙𝟏
𝟎 24) ∫
𝒙𝟐
𝒙𝟑+𝟐𝟕 𝒅𝒙
25) ∫ 𝒅𝒙
√𝟒−𝒙𝟐
𝟏
𝟎 26) ∫ 𝒚𝟐 (𝟑𝒚𝟑 + 𝟏)𝟒 𝒅𝒚
27) ∫𝒙
√𝟐𝟓−𝒙𝟐 𝒅𝒙
𝟑
𝟎 28) ∫ (𝟏 − 𝒄𝒐𝒔𝟐 𝟑𝜽) 𝒅𝜽
𝝅
𝟎
29) ∫ 𝒙 𝒔𝒊𝒏 𝒙𝟐 𝒄𝒐𝒔𝟖 𝒙 𝒅𝒙 30) ∫ 𝒔𝒊𝒏𝟐 𝟓𝜽 𝒅𝜽
31) ∫𝒙𝟐+𝟐𝒙−𝟐
𝒙𝟑+𝟑𝒙𝟐−𝟔𝒙 𝒅𝒙 32) ∫ (
𝒆𝒙
𝟏+𝒆𝟐𝒙)𝒍𝒏 𝟐
𝟎 𝒅𝒙
33) (Briggs Revision Ex.5 #38) Properties of integrals
The figure shows the areas of regions bounded by the graph of 𝒇 and the 𝒙-axis. Evaluate
the following integrals.
(a) ∫ 𝒇(𝒙) 𝒅𝒙𝒄
𝒂 (b) ∫ 𝒇(𝒙) 𝒅𝒙
𝒅
𝒃 (c) ∫ 𝟐 𝒇(𝒙) 𝒅𝒙
𝒃
𝒄
(d) ∫ 𝟒 𝒇(𝒙) 𝒅𝒙𝒅
𝒂 (e) ∫ 𝟑 𝒇(𝒙) 𝒅𝒙
𝒃
𝒂 (f) ∫ 𝟐 𝒇(𝒙) 𝒅𝒙
𝒅
𝒃
34) (Briggs Revision Ex.5 #52) Identifying functions Match the graphs A, B,
and C in the figure with the functions 𝑓(𝑥), 𝑓′(𝑥) and ∫ 𝑓(𝑡)𝑑𝑡𝑥
0 .
Additional Integral (Briggs Revision Ex.5 #56-61) Evaluate the following integrals.
35) ∫ 𝒔𝒊𝒏 𝟐𝒙
𝟏+𝒄𝒐𝒔𝟐 𝒙 𝒅𝒙 (Hint: 𝒔𝒊𝒏 𝟐𝒙 = 𝟐 𝒔𝒊𝒏 𝒙 𝒄𝒐𝒔 𝒙 )
36) ∫𝟏
𝒙𝟐 𝒔𝒊𝒏
𝟏
𝒙 𝒅𝒙 37) ∫
(𝒕𝒂𝒏−𝟏 𝒙)𝟓
𝟏+𝒙𝟐 𝒅𝒙 38)∫
𝒅𝒙
(𝒕𝒂𝒏−𝟏 𝒙)(𝟏+𝒙𝟐)
39) ∫ 𝒔𝒊𝒏−𝟏 𝒙
√𝟏−𝒙𝟐 𝒅𝒙 40) ∫
𝒆𝒙−𝒆−𝒙
𝒆𝒙+𝒆−𝒙 𝒅𝒙