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    Test - 6_Code - C_(Paper - II) (Answers & Hints) All India Aakash Test Series for JEE (Advanced)-2015

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    PHYSICS

    1. (B)

    2. (B)

    3. (C)

    4. (B)

    5. (B)

    6. (D)

    7. (D)

    8. (B, D)

    9. (A, B, D)

    10. (C, D)

    11. (A, D)

    12. (D)

    13. (A)

    14. (B)

    15. (C)

    16. (A)

    17. (A)

    18. (6)

    19. (4)

    20. (3)

    CHEMISTRY

    21. (C)

    22. (C)

    23. (B)

    24. (C)

    25. (B)

    26. (C)

    27. (A, B, C, D)

    28. (A, B, C, D)

    29. (A, B)

    30. (B, D)

    31. (A, C)

    32. (C)

    33. (C)

    34. (C)

    35. (A)

    36. (C)

    37. (B)

    38. (6)

    39. (5)

    40. (4)

    MATHEMATICS

    41. (B)

    42. (B)

    43. (A)

    44. (C)

    45. (A)

    46. (B)

    47. (A, B, C, D)

    48. (A, C, D)

    49. (A, C)

    50. (A, C)

    51. (C, D)

    52. (A)

    53. (D)

    54. (A)

    55. (B)

    56. (B)

    57. (D)

    58. (2)

    59. (4)

    60. (9)

    ANSWERS

    TEST - 6 (Paper-II) - Code-C

    All India Aakash Test Series for JEE (Advanced)-2015

    Test Date : 01-02-2015

    Click here for Code-D Solution

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    1. Answer (B)

    2. Answer (B)

    3. Answer (C)

    r

    r

    r(1 cos) =x ...(i)

    rsin= y ...(ii)

    From (i) & (ii)

    Momentum =

    2

    2

    qB yx

    x

    4. Answer (B)

    5. Answer (B)

    F= eE= 2

    r dB

    edt

    6. Answer (D)

    At = 0

    z=

    i= 0

    7. Answer (D)

    8. Answer (B, D)

    9. Answer (A, B, D)

    10. Answer (C, D)

    11. Answer (A, D)

    qvBl

    C i= avBl

    mg ilB= ma

    mg avl2B2= ma

    2 2 constant

    ( )

    mga

    m vl B

    12. Answer (D)

    PART - I (PHYSICS)

    ANSWERS & HINTS

    13. Answer (A)

    21

    2qEr mv (i)

    2qEr

    vm

    2

    2 1

    B E

    mvN F F N

    r (ii)

    2

    2 1 0

    E B

    mvN N F F

    r (iii) [Given]

    2

    2

    9

    qB rEm

    14. Answer (B)

    i= 0.5 Wb

    f= 2 Wb

    = 1.5 Wb

    15. Answer (C)

    16. Answer (A)

    17. Answer (A)

    18. Answer (6)

    When iis max V2C

    = V3C

    Common potential =1 1 2 2

    1 2

    C V C V

    C C

    =0 0

    73 2

    2

    3 2

    C V C V

    C C

    = 2V0

    2 20 01

    (3 ) 4 62

    U C V CV

    19. Answer (4)

    qvBl

    C (i)

    i

    aBlC

    (ii)

    Now, kx ilB= ma (iii)

    kx CaB2l2= ma

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    kx= (CB2l2+ m)a

    2 2

    ka x

    CB l m

    2 2

    2 m B l C

    T

    k

    Time =4

    T

    21. Answer (C)

    w

    h

    a

    KK

    K

    Here Ka is the ionization constant of parent acid and

    H

    is the weakest acid so, its Kh is

    highest.

    22. Answer (C)

    Nitro group stabilizes phenoxide ion formed and

    steric inhibition of resonance of NO2stop stablizationof phenoxide ion by resonance. So, p-nitrophenol is

    most acidic.

    23. Answer (B)

    Bulky groups at equitorial positions brings most

    stable conformer.

    24. Answer (C)

    is crystalizes as ionic solid by keeping

    negative terminal at five membered ring and positive

    terminal on seven membered ring in order to maintain

    aromaticity.

    25. Answer (B)

    O

    O

    O HH O

    OH

    OHH

    IIIII

    I

    IV

    20. Answer (3)

    B= 012 cos 30 cos 604 3

    2

    i

    l

    B= 0 3 3 1il

    PART - II (CHEMISTRY)

    From I to II to III it is a clockwise movement hence,

    configuration at Cis R.

    O

    O

    O HH O

    OH

    OHH

    III

    I

    II

    *

    H

    From I to II to III it is a anticlockwise movement

    hence, configuration at C* is S.

    26. Answer (C)

    Molecule as per Newman projection is

    H

    CH3

    H

    H3C

    Cis(1, 4) dimethylcyclohexane

    27. Answer (A, B, C, D)

    2HCl D O HOD DCl

    In solution available electrophiles are H+and D+. So,

    probable products are

    OD

    H

    ,

    OD

    D

    ,

    OD

    H

    ,

    OD

    D

    28. Answer (A, B, C, D)

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    29. Answer (A, B)

    Claisen rearrangement mechanism is completely

    concerted hence, no crossover product formation is

    observed.

    30. Answer (B, D)

    LiAlH4is not able to reduce unconjugated C C .

    31. Answer (A, C)

    In case of t-butylbenzene because of the stability of

    , electrophile NO2substitute t-butyl group.

    32. Answer (C)

    33. Answer (C)

    Basic strength of amines is also dependent on steric

    hinderence of the group bonded to N and hydration.

    34. Answer (C)

    O H O

    H H

    Cl Cl

    D D

    NH2

    OH

    D

    35. Answer (A)

    36. Answer (C)

    (P)

    OO O

    ClHO

    (i) LiAlH4

    (ii) H O2

    OH

    OHHO

    DBE = 2

    (Q)

    OO

    HO

    C NNaBH

    4

    H O2

    OHO

    HO

    C N

    DBE = 5

    (R) Cold alk.

    KMnO4

    OH

    OH

    OHOH

    OH

    HO

    DBE = 1

    (S) mCPBA

    O

    O

    O

    DBE = 4

    37. Answer (B)

    In aqueous medium down the group nucleophilicity

    increases, across the period nucleophilicity

    increases. Anions are better nucleophile than neutral

    ones and nucleophilicity decreases as steric

    hinderence increases.

    38. Answer (6)

    Cl

    H H

    Cl

    H

    Cl

    H

    Cl

    H

    Cl

    Cl

    HCl

    Cl Cl

    H

    Cl H

    Cl

    H Cl

    H

    Six sterioisomers are formed.

    39. Answer (5)

    (1), (3), (5), (7) and (9) show Walden inversion in SN2.

    40. Answer (4)

    Hydrogen from phenolic group, COOH, SH and

    C

    NH

    C

    OO

    are removed from NaOH.

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    41. Answer (B)

    Length of sub-normal = length of sub-tangent

    1 dy

    dx

    If 1dy

    dx, equation of the tangent y 4 =x 3

    yx= 1, area of OAB=1 1

    1 12 2

    If 1dy

    dx, equation of the tangent is y 4 = x+ 3

    y+x= 7, area =

    1 497 7

    2 2

    42. Answer (B)

    v=x3and the percent error in measuring edge =

    100dx

    Kx

    The percent error in measuring volume = 100dv

    v

    Now, 23dv

    xdx

    dv= 3x2dx

    2

    3

    3 3

    dv x dx dx

    v xx

    3

    100 100 3 dv dx

    Kv x

    43. Answer (A)

    f(x) = (x 2)(x 3) x3

    = (x 2)(x 3) x< 3

    Graph of f(x) isy

    0 2 3 x

    5

    2

    Clearly f(x) is increasing in 5

    , 3,2

    44. Answer (C)

    log 1 1

    x x

    x x

    x

    e e

    I e e dx e

    =

    log 11

    x

    x x

    x

    ee e dx

    e

    = log 1 log 1 x x xe e e C

    = exlog(ex+ 1) log(1 + ex) +x+ C

    = 1 log 1x xe e x C

    45. Answer (A)

    5

    4

    3 44

    2 cos 4

    1

    x

    x dx

    I

    e

    Put 4

    x t

    2 cos

    1

    t

    tI

    e

    2cos( )

    1

    tt

    I

    e

    Adding

    2 2 cos 0

    I t I= 0

    46. Answer (B)

    0 x< 1

    y= [x+ 1] = 1

    So required area =

    1

    0

    ydy

    =

    13

    2

    0

    2

    3

    y

    = 2 sq. unit3

    PART - III (MATHEMATICS)

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    47. Answer (A, B, C, D)

    Here dy y

    dx a

    Sub-tangent = constant

    y

    ady

    dx

    Sub-normal =2dy y y

    y ydx a a

    Equation of tangent at (x1, y

    1) is

    11 1 ( )

    yy y x x

    a

    This meets thex-axis at a point given by

    1

    1 1 [ ]

    y

    y x xa

    x=x1 a

    The curve meets the y-axis at (0, C)

    (0, )

    c

    dy c

    dx a

    Equation of normal 1

    ( 0)y c xc

    a

    ax+ cy= c2

    48. Answer (A, C, D)

    Graph of f(x)

    y

    21x

    When is evenn

    y

    21x

    When is oddn

    49. Answer (A, C)

    2

    3

    2 2

    1

    1

    xx x

    I e dx

    x

    =

    2

    3 3

    22 2 2

    1

    1( 1)

    x x x

    e dx

    xx

    =32

    2 2

    1

    1( 1)

    x x

    e dx

    xx

    = ( ) ( ) x

    e f x f x dx where2

    1( )

    1

    f x

    x

    2

    ( )

    1

    x

    x ee f x c c

    x

    f(x) =2

    1

    1x

    50. Answer (A, C)

    Let f(x) = 33 x

    Clearly f(x) is increasing in [1, 3]

    The least value of function m= f(1) = 33 1 2

    & maximum value M= f(3) = 33 3 30

    Therefore,

    3

    2

    1

    (3 1) 2 3 (3 1) 30x dx

    So

    2

    3

    1

    4 3 2 30x dx

    51. Answer (C, D)

    Since the curve

    1

    2

    y ax bx passes through thepoint (1, 2)

    2 = a+ b ...(i)

    By observation the curve also passes through (0, 0)

    14

    2

    0

    8A ax bx dx

    2

    8 16 83 2

    a b

    2

    13

    ab ...(ii)

    Solving (i) & (ii) we get a= 3, b= 1

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    52. Answer (A)

    h(x) = f(x) a((f(x))2+ a(f(x))3)

    h(x) = f(x) 2a f(x) f(x) + 3a(f(x))2f(x)

    h(x) = f(x) [3a[f(x)]2 2af(x) + 1]

    Now h(x) increases if f(x) increases and

    3a(f(x))2 2af(x) + 1 > 0 x R

    3a> 0 & 4a2 12a0

    a> 0 & a[0, 3]

    a[0, 3]

    53. Answer (D)

    h(x) is non-monotonic functions if

    3a(f(x))2 2a f(x) + 1 changes sign for which D0 or

    4a2 12a0

    a(, 0] [3, )54. Answer (A)

    Put 1 +x= t6

    To get3

    61

    t

    I dtt

    =3

    1 16

    1

    t

    dtt

    =2 1

    6 1 1

    t t dt t

    = 1 11 1

    6 62 32 1 3 1 6(1 ) 6ln (1 ) 1x x x x c

    55. Answer (B)

    Let 2 2

    2

    xt

    x

    2

    2 1

    2

    x

    x t

    by C & D

    2

    2

    12

    1

    tx

    t

    2 2

    2 2 22

    (1 )2 (1 )2 82

    (1 ) 1

    t t t t t dx dt dt

    t t

    2

    2 2 2

    1 1 8

    2 1 (1 )

    t tt dt

    t t

    =

    2

    2 24

    1 1

    tdt

    t t

    2 22

    1 1

    dt dt

    t t

    11log 2 tan1

    tt C

    t

    where

    2

    2

    xt

    x

    56. Answer (B)

    57. Answer (D)

    58. Answer (2)

    1

    0

    (2 )I xf x dx , Put 2x= t

    2

    dtdx

    So

    2

    0

    1( )

    4I tf t dt

    Apply by parts to solve the integral.

    59. Answer (4)

    x1

    22 2 32 2

    00 0

    8 4(2 ) 4 4

    3 3 3

    yA xdy y y dy

    60. Answer (9)

    Differentiating the curve we get

    6 8 0dy

    x ydx

    ( , )

    3 3

    4 2a b

    dy a

    dx b

    2a

    b ...(i)

    Also (a, b) lies on the curve

    So

    3a2 4b2= 72 ...(ii)

    Solving (i) & (ii) we get a= 6

    & b= 3

    Out of (6, 3) & (6, 3), (6, 3) is closer to line

    So a= 6 & b= 3

    b a= 9

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    PHYSICS

    1. (D)

    2. (B)

    3. (B)

    4. (C)

    5. (B)

    6. (B)

    7. (A, D)

    8. (C, D)

    9. (A, B, D)

    10. (B, D)

    11. (D)

    12. (B)

    13. (C)

    14. (D)

    15. (A)

    16. (A)

    17. (A)

    18. (3)

    19. (4)

    20. (6)

    CHEMISTRY

    21. (C)

    22. (B)

    23. (C)

    24. (B)

    25. (C)

    26. (C)

    27. (A, C)

    28. (B, D)

    29. (A, B)

    30. (A, B, C, D)

    31. (A, B, C, D)

    32. (C)

    33. (A)

    34. (C)

    35. (C)

    36. (B)

    37. (C)

    38. (4)

    39. (5)

    40. (6)

    MATHEMATICS

    41. (B)

    42. (A)

    43. (C)

    44. (A)

    45. (B)

    46. (B)

    47. (C, D)

    48. (A, C)

    49. (A, C)

    50. (A, C, D)

    51. (A, B, C, D)

    52. (A)

    53. (B)

    54. (A)

    55. (D)

    56. (D)

    57. (B)

    58. (9)

    59. (4)

    60. (2)

    ANSWERS

    TEST - 6 (Paper-II) - Code-D

    All India Aakash Test Series for JEE (Advanced)-2015

    Test Date : 01-02-2015

    Click here Code-C Solution

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    1. Answer (D)

    At = 0

    z=

    i= 0

    2. Answer (B)

    F= eE=2

    r dBe

    dt

    3. Answer (B)

    4. Answer (C)

    r

    r

    r(1 cos) =x ...(i)

    rsin= y ...(ii)

    From (i) & (ii)

    Momentum =

    2

    2

    qB yxx

    5. Answer (B)

    6. Answer (B)

    7. Answer (A, D)

    qvBl

    C i= avBl

    mg ilB= ma

    mg avl2B2= ma

    2 2 constant

    ( )mga

    m vl B

    8. Answer (C, D)

    9. Answer (A, B, D)

    10. Answer (B, D)

    11. Answer (D)

    12. Answer (B)

    i= 0.5 Wb

    f= 2 Wb

    = 1.5 Wb

    PART - I (PHYSICS)

    ANSWERS & HINTS

    13. Answer (C)

    14. Answer (D)

    15. Answer (A)

    21

    2qEr mv (i)

    2qEr

    vm

    2

    2 1

    B E

    mvN F F N

    r (ii)

    2

    2 1 0

    E BmvN N F F

    r (iii) [Given]

    22

    9

    qB rE

    m

    16. Answer (A)

    17. Answer (A)

    18. Answer (3)

    B= 0

    12 cos 30 cos 604 3

    2

    i

    l

    B= 0 3 3 1il

    19. Answer (4)

    qvBl

    C (i)

    i

    aBl

    C

    (ii)

    Now, kx ilB= ma (iii)

    kx CaB2l2= ma

    kx= (CB2l2+ m)a

    2 2

    ka x

    CB l m

    2 2

    2 m B l C

    Tk

    Time =4

    T

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    20. Answer (6)

    When iis max V2C

    = V3C

    Common potential =1 1 2 2

    1 2

    C V C V

    C C

    21. Answer (C)

    Molecule as per Newman projection is

    H

    CH3

    H

    H3C

    Cis(1, 4) dimethylcyclohexane

    22. Answer (B)

    O

    O

    O HH O

    OH

    OHH

    IIIII

    I

    IV

    From I to II to III it is a clockwise movement hence,

    configuration at Cis R.

    O

    O

    O HH O

    OH

    OHH

    III

    I

    II

    *

    H

    From I to II to III it is a anticlockwise movement

    hence, configuration at C* is S.

    23. Answer (C)

    is crystalizes as ionic solid by keeping

    negative terminal at five membered ring and positive

    terminal on seven membered ring in order to maintain

    aromaticity.

    =0 0

    73 2

    2

    3 2

    C V C V

    C C

    = 2V0

    2 20 01 (3 ) 4 62U C V CV

    PART - II (CHEMISTRY)

    24. Answer (B)

    Bulky groups at equitorial positions brings most

    stable conformer.

    25. Answer (C)

    Nitro group stabilizes phenoxide ion formed andsteric inhibition of resonance of NO

    2stop stablization

    of phenoxide ion by resonance. So, p-nitrophenol is

    most acidic.

    26. Answer (C)

    w

    h

    a

    KK

    K

    Here Ka is the ionization constant of parent acid and

    H

    is the weakest acid so, its Kh is

    highest.

    27. Answer (A, C)

    In case of t-butylbenzene because of the stability of

    , electrophile NO2substitute t-butyl group.

    28. Answer (B, D)

    LiAlH4is not able to reduce unconjugated C C .

    29. Answer (A, B)

    Claisen rearrangement mechanism is completely

    concerted hence, no crossover product formation is

    observed.

    30. Answer (A, B, C, D)

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    31. Answer (A, B, C, D)

    2HCl D O HOD DCl

    In solution available electrophiles are H+and D+. So,

    probable products are

    OD

    H

    ,

    OD

    D

    ,

    OD

    H

    ,

    OD

    D

    32. Answer (C)

    O H O

    H H

    Cl Cl

    D D

    NH2

    OH

    D

    33. Answer (A)

    34. Answer (C)

    35. Answer (C)

    Basic strength of amines is also dependent on steric

    hinderence of the group bonded to N and hydration.

    36. Answer (B)

    In aqueous medium down the group nucleophilicity

    increases, across the period nucleophilicity

    increases. Anions are better nucleophile than neutral

    ones and nucleophilicity decreases as steric

    hinderence increases.

    37. Answer (C)

    (P)

    OO O

    ClHO

    (i) LiAlH4

    (ii) H O2

    OH

    OHHO

    DBE = 2

    (Q)

    OO

    HO

    C NNaBH

    4

    H O2

    OHO

    HO

    C N

    DBE = 5

    (R) Cold alk.

    KMnO4

    OH

    OH

    OHOH

    OH

    HO

    DBE = 1

    (S) mCPBA

    O

    O

    O

    DBE = 4

    38. Answer (4)

    Hydrogen from phenolic group, COOH, SH and

    C

    NH

    C

    OO

    are removed from NaOH.

    39. Answer (5)

    (1), (3), (5), (7) and (9) show Walden inversion in SN2.

    40. Answer (6)

    Cl

    H H

    Cl

    H

    Cl

    H

    Cl

    H

    Cl

    Cl

    HCl

    Cl Cl

    H

    Cl H

    Cl

    H Cl

    H

    Six sterioisomers are formed.

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    41. Answer (B)

    0 x< 1

    y= [x+ 1] = 1

    So required area =

    1

    0

    ydy

    =

    13

    2

    0

    2

    3

    y

    =2

    sq. unit3

    42. Answer (A)

    5

    4

    3 44

    2 cos 4

    1

    x

    x dx

    I

    e

    Put 4

    x t

    2 cos

    1

    tt

    I

    e

    2cos( )

    1

    tt

    I

    e

    Adding

    2 2 cos 0

    I t I= 0

    43. Answer (C)

    log 11

    x xx x

    x

    e eI e e dx

    e

    =

    log 11

    x

    x x

    x

    ee e dx

    e

    = log 1 log 1 x x xe e e C

    = exlog(ex+ 1) log(1 + ex) +x+ C

    = 1 log 1x xe e x C

    44. Answer (A)

    f(x) = (x 2)(x 3) x3

    = (x 2)(x 3) x< 3

    Graph of f(x) is

    y

    0 2 3 x

    5

    2

    Clearly f(x) is increasing in 5 , 3,2

    45. Answer (B)

    v=x3and the percent error in measuring edge =

    100dx

    Kx

    The percent error in measuring volume = 100dv

    v

    Now,

    23

    dvx

    dx

    dv= 3x2dx

    2

    3

    3 3

    dv x dx dx

    v xx

    3

    100 100 3 dv dx

    Kv x

    46. Answer (B)

    Length of sub-normal = length of sub-tangent

    1 dy

    dx

    If 1dy

    dx, equation of the tangent y 4 =x 3

    yx= 1, area of OAB=1 1

    1 12 2

    If 1dy

    dx, equation of the tangent is y 4 = x+ 3

    y+x= 7, area =

    1 497 7

    2 2

    PART - III (MATHEMATICS)

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    47. Answer (C, D)

    Since the curve

    1

    2 y ax bx passes through the

    point (1, 2)

    2 = a+ b ...(i)By observation the curve also passes through (0, 0)

    14

    2

    0

    8A ax bx dx

    2

    8 16 83 2

    a b

    2

    13

    ab ...(ii)

    Solving (i) & (ii) we get a= 3, b= 1

    48. Answer (A, C)

    Let f(x) = 33 x

    Clearly f(x) is increasing in [1, 3]

    The least value of function m= f(1) = 33 1 2

    & maximum value M= f(3) =3

    3 3 30

    Therefore,

    3

    2

    1

    (3 1) 2 3 (3 1) 30x dx

    So

    2

    3

    1

    4 3 2 30x dx

    49. Answer (A, C)

    2

    3

    2 2

    1

    1

    xx x

    I e dx

    x

    =

    2

    3 3

    22 2 2

    1

    1( 1)

    x x x

    e dx

    xx

    =32

    2 2

    1

    1( 1)

    x x

    e dx

    xx

    = ( ) ( ) x

    e f x f x dx where2

    1( )

    1

    f x

    x

    2 ( )

    1

    x

    x ee f x c c

    x f(x) = 2

    1

    1x

    50. Answer (A, C, D)

    Graph of f(x)

    y

    21x

    When is evenn

    y

    21x

    When is oddn

    51. Answer (A, B, C, D)

    Here dy y

    dx a

    Sub-tangent = constanty

    ady

    dx

    Sub-normal =2dy y y

    y ydx a a

    Equation of tangent at (x1, y

    1) is

    11 1 ( )

    yy y x x

    a

    This meets thex-axis at a point given by

    1

    1 1 [ ]

    y

    y x xa

    x=x1 a

    The curve meets the y-axis at (0, C)

    (0, )

    c

    dy c

    dx a

    Equation of normal 1

    ( 0)y c xc

    a

    ax+ cy= c2

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    52. Answer (A)

    Put 1 +x= t6

    To get3

    61

    t

    I dtt

    =3 1 1

    6 1

    t

    dtt

    =2 1

    6 1 1

    t t dt t

    = 1 1

    1 1

    6 62 32 1 3 1 6(1 ) 6ln (1 ) 1x x x x c

    53. Answer (B)

    Let 2 2

    2

    xt

    x

    2

    2 1

    2

    x

    x t

    by C & D

    2

    2

    12

    1

    tx

    t

    2 2

    2 2 22

    (1 )2 (1 )2 82

    (1 ) 1

    t t t t t dx dt dt

    t t

    2

    2 2 2

    1 1 8

    2 1 (1 )

    t tt dt

    t t

    =

    2

    2 24

    1 1

    tdt

    t t

    2 22 1 1

    dt dt

    t t

    11log 2 tan

    1

    tt C

    t

    where

    2

    2

    xt

    x

    54. Answer (A)

    h(x) = f(x) a((f(x))2+ a(f(x))3)

    h(x) = f(x) 2a f(x) f(x) + 3a(f(x))2f(x)

    h(x) = f(x) [3a[f(x)]2 2af(x) + 1]

    Now h(x) increases if f(x) increases and

    3a(f(x))

    2

    2af(x) + 1 > 0x R

    3a> 0 & 4a2 12a0

    a> 0 & a[0, 3]

    a[0, 3]

    55. Answer (D)

    h(x) is non-monotonic functions if

    3a(f(x))2 2a f(x) + 1 changes sign for which D0 or

    4a2 12a0

    a(, 0] [3, )

    56. Answer (D)

    57. Answer (B)

    58. Answer (9)

    Differentiating the curve we get

    6 8 0dy

    x ydx

    ( , )

    3 3

    4 2a b

    dy a

    dx b

    2a

    b ...(i)

    Also (a, b) lies on the curve

    So

    3a2

    4b2

    = 72 ...(ii)Solving (i) & (ii) we get a= 6

    & b= 3

    Out of (6, 3) & (6, 3), (6, 3) is closer to line

    So a= 6 & b= 3

    b a= 9

    59. Answer (4)

    x1

    22 2 32 2

    00 0

    8 4(2 ) 4 4

    3 3 3

    yA xdy y y dy

    60. Answer (2)

    1

    0

    (2 )I xf x dx , Put 2x= t

    2

    dtdx

    So

    2

    0

    1( )

    4I tf t dt

    Apply by parts to solve the integral.