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    Topic wise Previous IIT JEE Mathematics Questions

    Complex numbers

    01. If |z| =1 and z 1 , then all the values of2

    z

    1 zlie on

    a) a line not passing through the origin b) |z| = 2

    c) the x-axis d) the y-axis Ans. d

    02. A particle P starts from the point z0 = 1+2i, where i 1= . It moves first horizontally a way from

    origin by 5 units and then vertically a way from origin by 3 units to reach a point z1. From z1 the

    particle moves 2 units in the direction of the vector i + j and then it moves though an angle2

    in

    anticlockwise direction on a circle with centre at origin, to reach a point z2. The point z2 is given by

    a) 6 + 7i b) -7 + 6i Ans. d

    c) 7 + 6i d) -6 + 7i

    Paragraph question

    Let A, B, C be three sets of complex numbers as defined as follows:

    A = { z : Im (z) 1}

    B = {z: |z -2 i| = 3

    C = {z: Re ((1-i)z) = 2 }

    03. Then number of elements in the set A B C is Ans. b

    a) 0 b) 1 c) 2 d)

    04. Let z be any point in A B C . Then |z + 1 i|2 + |z 5 i|2 lie between

    a) 25 and 29 b) 30 and 34 Ans. c

    c) 35 and 39 d) 40 and 44

    05. Let z be any point in A B C and let w be any point satisfying |w 2- i|

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    a)2

    (p q)(2q p)9

    b)2

    (q p)(2p q)9

    c)2

    (q 2p)(2q p)9

    d)2

    (2p q)(2q p)9

    07. Let a, b, c, p, q be real numbers. Suppose , are the roots of the equation x2 + 2px+q=0 and1

    ,

    are

    the roots of the equation ax2+2bx+c=0, where

    2{ 1,0,1} . Ans. b

    Statement-1 :2 2

    (p q)(b ac) 0

    Statement -2 b pa or c qa

    Progression

    08. If x is the fist term of an infinite G.P., whose sum is 10, then Ans. a

    a) 0 < x < 10 b) -5 < x < 5 c) -10 < x < 10 d) x 10

    Reasoning type

    09. Suppose four distinct positive numbers a1, a2, a3, a4 are in G.P. Let b1 = a1, b2 = b1 + a2, b3 = b2 + a3 and

    b4 = b3 + a4.

    Statement 1 : The numbers b1, b2, b3, b4 are neither in A.P nor in G.P

    Statement 2: The numbers b1, b2, b3, b4 are in H.P. Ans. d

    Logarithm

    10. If x > 1, y < 1, z < 1 are in G.P., then1 1 1

    , ,1 logx 1 log y 1 logz+ + +

    are in

    a) A.P. b) H.P Ans. b

    c) G.P d) None of these

    11. The number of solutions of log4 (x-1) = log2(x 3) Ans. b

    a) 3 b) 1 c) 2 d) 0

    Permutations and Combinations

    12. The letters of the word COCHIN are permuted and all permutations are arranged in an alphabetical

    order as in an English dictionary. The number of words that appear before the word COCHIN is

    Ans. c

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    a) 36 b) 192 c) 96 d) 48

    13. Consider all possible permutations of the letters of the word ENDEANOEL. Match the entries in

    Column I with the correctly related quantum number(s) in Column II. Indicate your answer by

    darkening the appropriate bubbles of the 4 4 matrix given in the ORS.

    Column I Column II

    a) The number of permutations p) 5!

    b) The number of permutations in q) 2 5!

    which the letter E occurs in the

    first and the lat positions is

    c) The number of permutations in r) 7 5!

    which none of the letters D, L, N

    occurs in the last five positions is

    d) The number of permutations in s) 21 5!

    which the letters A, E, O occur only

    in odd positions is

    Ans:

    p q r s

    a p q r s

    b p q r s

    c p q r s

    d p q r s

    Binomial Theorem

    14. If n and k are positive integers, show that

    k k 1 k 2n n n n 1

    2 2 20 k 1 k 1

    +

    n n 2

    2 k 2

    -+

    kn n k n

    ( 1)k 0 k

    =

    wheren

    k

    stands forn

    kC .

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    15. If n

    k

    stands forn

    rC , the value of

    30 30 30 30

    0 10 1 11

    +

    30 30 30 30....

    2 12 20 30

    +

    is Ans. a

    a)

    30

    10

    b)

    30

    15

    c)

    31

    11

    d)

    60

    30

    Matrices

    16. Let a, b and c be three distinct real numbers and f(x) be a quadratic polynomial satisfying the equation

    2

    2

    2

    4a 4a 1

    4b 4b 1

    4c 4c 1

    f( 1)

    f (1)

    f(2)

    =

    2

    2

    2

    3a 3a

    3b 3b

    3c 3c

    +

    + +

    Let V be the point of local maxima of y = f(x) and A be the point where y=f(x) meets the x-axis and B

    be a point on y=f(x) such that AB subtends a right angle at V. Find the area of the region lying

    between the curve and chord AB.

    Ans. 2125

    (unit)3

    Passage type question

    Let

    1 0 0

    2 1 03 2 1

    and X1, X2, X3 be three column matrices such that

    1 2

    1 2

    AX 0 ,AX 3

    0 0

    = =

    and 3

    2

    AX 3

    1

    =

    and let X be a 3 3 matrix whose columns are X1, X2, X3.

    17. Value of det (x) is Ans. c

    a) -2 b) -1 c) 3 d) 0

    18. Sum of the elements of X-1 is Ans. b

    a) -1 b) 0 c) 4 d)

    19. If [a] = [3 2 0] X

    3

    2

    0

    . Then a equals Ans. a

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    a) 5 b) 4 c) 3/2 d) 5/2

    Determinants

    20. The value of for which the system of equations x y z 4+ + = , x 2y z 4 0 + + = , 2x-y-z=2 has no

    solution is Ans. b

    a) - 3 b) 2 c) 0 d) 3

    21. Reasoning type Ans. b

    Consier the system of equations ax+by =0, cx + dy = 0, where a, b, c, d {0, 1} Statement 1 : The

    probability that the system of equations has a unique solution is 3/8

    Statemet 2 : The probability that the system of equations has a solutions is 1.

    INEQUALITIES

    22. A straight line through the vertex P of a triangle PQR intersects the side QR at the point S and the

    circumcircle of the triangle PQR at the point T. If S is not the centre of the circumcircle, then

    Ans. b, d

    a)1 1 2

    PS ST QS SR+

    c)1 1 4

    PS ST QR+ < d)

    1 1 4

    PS ST QR+ >

    23. Letn

    n 2 2k 1

    nS

    n kn k ==

    + + and Tn =

    n 1

    2 2k 0

    n

    n kn k

    = + + , for n=1, 2, 3,, Then.

    a) Sn

    3 3

    c) nT

    3 3

    < d) nT

    3 3

    >

    Ans. a, c

    PROBABILITY

    24. Let E denotes the complement of an event E. Let E, F, G be pair wise independent events such that

    P(G)>0 and P(E F )=0. Then P(E FG) equals Ans. c

    a) P(E) + P(F) b) P(E)-P(F) c) P(E)-P(F) d) P(E)-P(F)

    25. Reasoning type Ans. b

    Consider the system of equations

    ax + by = 0, cx + dy = 0, where a,b,c,d {0, 1}

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    Statement -1: The probability that the system of equations has a unique solution is3

    8.

    Statement 2 : The probability that the system of equations has a solution is 1.

    ELEMENTARY TRIGONOMETRY

    26. If and are acute angles such that sin = , cos = 1/3, then + lies in

    a) ] / 3, / 2[ b) ] / 2, 2 /3[

    3. ]2 /3, 4 /3[ d) None of these Ans. b

    27. Given (0, / 4), and tan1t (tan )= t2 =

    cot(tan ) tan3t (cot )

    = and cot4t (cot )= then

    a) t1 > t2 > t3 > t4 b) t4 > t3 > t1 > t2

    c) t3 > t1 > t2 > t4 d) t2 > t3 > t1 > t4 Ans. b

    SOLUTION OF TRIANGLES AND APPLICATIONS OF TRIGONOMETRY

    28. If a, b, c denote the lengths of the sides of a triangle opposite angles A, B, C of a triangle ABC, then

    the correct relation among a, b, c, A, B and C is given by Ans. b

    a) (b + c) sin ((B + C)/2) = a cos (A/2)

    b) (b c) cos (A/2) = a sin ((B C)/2)

    c) (b c0 cos (A/2) = 2a sin ((B C)/20

    d) (b c) sin ((B C)/2) = a cos (A/2)

    29. Let a, b, c be the sides of a triangle. No two of them are euqlal and R. If the roots of the equations,

    x2+2(a+b+c)x+3 (ab+bc+ca)=0 are real, then Ans. a

    a) 4 / 3 < b) 5/ 3 >

    c) (1/ 3, 5 / 3) d) (4/ 3, 5/ 3)

    TRIGONOMETRIC EQUATIONS

    30. 0 2 , 22sin 5sin 2 0, + > then the range of is Ans. a

    a) (0, / 6) (5 / 5, 2 ) b) (0, 5 / 6) ( ,2 )

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    c) (0, / 6) ( , 2 ) d) None of these

    31. The number of solutions, of the pair of equations 22sin cos 2 0 = and 22cos 3sin 0 = in the

    interval [0, 2 ] is Ans. c

    a) 0 b) 1 c) 2 d) 4

    INVERSE TRIGONOMETRIC FUNCTIONS

    32. If 0 < x < 1, then 21 x+ [{xcos(cot-1x)+sin(cot-1x)}2-1]1/2 =1

    a)2

    x

    1 x+b) x

    c)2

    x 1 x+ d) 21 x+ Ans. c

    CARTESIAN SYSTEM OF RECTANGULAR COORDINATES AND

    STRAIGHT LINES

    33. Reasoning type Ans. c

    Lines L1: y x = 0 and L2: 2x + y = 0 intersect the line L3: y + 2 = 0 at P and Q respectively. The

    bisector of the acute angle between L1 and L2 intersect L3 = at R.

    Statement 1: The ratio PR: RQ equals 2 2 : 5 because

    Statement 2: In any triangle bisector of an angle divides the triangle into two similar triangles.

    34. Matrix match type

    L1: x+3y5=0, L2: 3x-ky-1=0, L3: 5x+2y-12=0

    Column I Column II

    a) L1, L2, L3 concurrent, if p) K = - 9

    b) One of L1, L2, L3 is parallel to at least q) K = -6/5

    one of the other two

    c) L1, L

    2, L

    3form a triangle r) K = 5/6

    d) L1, L2, L3 do not form a triangle s) K = -9

    Ans:

    p q r s

    a p q r s

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    b p q r s

    c p q r s

    d p q r s

    CIRCLES AND SYSTEM OF CIRCLES

    35. Let ABCD be a quadrilateral with area K, with side AB parallel to the side CD and AB = 2CD. Let AD

    be perpendicular to AB and CD. If a circle is drawn inside the quadrilateral ABCD touching all the

    sides, then its radius is Ans. b

    a) 3 b) 2 c) 3/2 d) 1

    36. Point E and F are given by Ans. a

    a) ( 3 / 2, 3/ 2), ( 3,0) b) ( 3 / 2, 1/ 2), ( 3,0)

    c) ( 3 / 2, 3/ 2), ( 3 / 2, 1/2) d) ( 3 /2, 3 /2 ), ( 3 /2, 1 /2)

    PAIR OF STRAIGHT LINES

    37. Area of the triangle formed by the angle bisectors of the pair of lines x2

    y2

    + 2y 1 =0 and the line

    x+y=3 (in square units) is Ans. b

    a) 1 b) 2 c) 3 d) 4

    38. Let a and b be non-zero real numbers. Then the equation2 2

    (ax by c)+ + 2 2(x 5xy 6y ) 0 + =

    represents Ans. b

    a) four straight lines, when c=0 and a, b are of the same sign.

    b) two straight lines and a circle, when a = b, and c is of sign opposite to that of a.

    c) Two straight lines and a hyperbola, when a and b are of the same sign and c is sign opposite to that

    of a.

    d) a circle and an ellipse, when a and b are of the same sign and c is of sign opposite to that of a .

    CONIC SECTION (PARABOLA, ELLIPSE, HYPERBOLA)

    39. Let P(x1, y1) and Q(x2, y2), y1

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    Ans. b, c

    40. Consider a branch of the hyperbola 2 2x 2y 2 2x 4 2y 6 0 = with vertex at the point A. Let B

    be one of the end points of its latus rectum. If C is the focus of the hyperbola nearest to the point A,

    then area of the triangle ABC is

    a) 1 2 / 3 b) 3 /2 -1

    c) 1 2 /3+ d) 1 3/ 2 1+ + Ans. b

    THREE DIMENSIONAL GEOMETRY

    41. Reasoning type

    Consider the planes 3x-6y-2z=15 and 2x+y-2z=5

    Statement -1: The parametric equations of the line of intersection of the given planes are x=3+14t,

    y=1+2t, z=15t.

    Statement 2: The vector 14i + 2j + 15k is parallel to the line of intersection of the given planes.

    Ans. d

    Linked comprehension type

    Consider the lines 1x 1 y 2 z 1

    L :3 1 2

    + + += = and

    2 x 2 y 2 z 3L :1 2 3 + = =

    42. The unit vector perpendicular to both L1 and L2 is Ans. b

    a)7 7

    99

    + +i j kb)

    7 5

    5 3

    +i j k

    c)7 5

    5 3

    + +i j kd)

    7 7

    99

    i j k

    43. The shortest distance between L1 and L2 is Ans. d

    a) 0 b) 17 / 3 c) 41/5 3 d) 17 /5 3

    44. The distance of the point (1, 1, 1) from the plane passing through the point (-1, -2, -1) and whose

    normal perpendicular to both the lines L1 and L2 is Ans. c

    a) 2 / 75 b) 7 / 75 c) 13/ 75 d) 23/ 75

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    VECTOR ALGEBRA

    45. The number of distinct real values of for which the vectors 2 , + +i j k 2 , +i j k and2

    ,+ i j k are coplanar, is Ans. c

    a) zero b) one c) two d) three

    46. The edges of a parallelepiped are of unit lengths and are parallel to non-coplanar unit vectors a, b, c

    such that a. b = b. c=c. a=1/2. Then the volume of the parallelepiped is

    a)1

    2b)

    1

    2 2Ans. a

    c)3

    2d)

    1

    3

    FUNCTIONS

    47. Let X and Y are two nonempty sets. Let f: X Y be a function. For A X and B Y, define1

    f(A) {f(x):x A}f (B)= = {x X / f (x) B} , then

    a) 1f (f (B)) B = b) 1f (f (B)) B

    c)1

    f (f (A)) A = d) 1f (f (A)) A Ans. b

    LIMITS AND CONTINUITY

    48. If 2x 0

    ((a n)nx tan x)sin nx

    lim x

    = 0, where n is a nonzero real numbers, then a is equal to

    a) 0 b)n

    n 1+Ans. d

    c) n d) n + 1/n

    49. For x > 0,1/ x sin x

    x 0lim ((sin x) (1/x) )

    + is Ans. c

    a) 0 b) -1 c) 1 d) 2

    DIFFERENTIATION

    50.2

    2

    d x

    dyequals Ans. b

    a)

    12

    2

    d y

    dx

    b)

    12

    2

    d y

    dx

    3dy

    dx

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    c)

    22

    2

    d y dy

    dx dx

    d)

    32

    2

    d y dy

    dx dx

    51. Let g(x) =4

    m

    (x 1);

    logcos (x 1)

    0 < x < 2, m and n are integers, m 0, n > 0, and let p be the left hand

    derivative of |x -1 | at x =1. Ifx 1limg(x) p,

    = then Ans. c

    a) n = 1, m = 1 b) n =1, m = -1

    c) n = 2, m = 2 d) n > 2, m = n

    APPLICATIONS OF DERIVATIVES

    52. The tangent to the curve y=ex

    drawn at the point (c, ec) intersects the line joining the points (c -1, e

    c-1)

    and (c+1, ec+1

    ) Ans. a

    a) on the left of x = c b) on the right of x = c

    c) at no point d) at all point

    53. Let the function g : ( , ) ( / 2, / 2) be given by g(u) =2 tan-1 (eu)- / 2, then g is

    a) even and is strictly increasing in (0, ) Ans. c

    b) odd and is strictly decreasing in ( , )

    c) odd and is strictly increasing in ( , )

    d) neither even nor odd, but in strictly increasing in ( , )

    INDEFINITE INTEGRAION

    54. Reasoning type Ans. d

    Let F(x) be an indefinite integral of sin2

    x.

    Statement 1 : The function F(x) satisfies F(x+ ) = F(x) for all real x.

    Statement 2 :2 2

    sin ( x) sin x + = for all real x.

    55. Letx

    4x 2x

    eI dx,

    e e 1=

    + +x

    4x 2x

    eJ dx

    e e 1

    =

    + +. Then for an arbitrary constant C, the value of J-I

    equals Ans. c

    a)1

    2log

    4x 2x

    4x x

    e e 1

    e e 1

    +

    + + + C b)

    2x x

    2x x

    1 e e 1log

    2 e e 1

    + +

    + + C

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    c)2x x

    2x x

    1 e e 1log

    2 e e 1

    +

    + + + C d)

    4x 2x

    4x 2x

    1 e e 1log

    2 e e 1

    + +

    + + C

    DEFINITE INTEGRALS

    56.

    2sec

    2

    2 2x / 4

    f(t) dt

    lim x /16

    equals Ans. a

    a)8

    f(2)

    b)2

    f(2)

    3.2 1

    f2

    4. 4f(2)

    57. Multiple correct answer type

    Let f(x) be a non constant twice differentiable function defined on ( , ) such that f(x) = f(1-x) and

    1f ' 0

    4

    =

    Then Ans. a, b, c, d

    a) f(x) vanishes at lest twice on [0, 1] b) f1

    2

    = 0

    c)

    1/ 2

    1/ 2

    1f x

    2

    +

    sin x dx = 0 d)

    1/ 2

    sin t

    0

    f(t)e 1

    sin t

    1/ 2

    dt f (1 t)e = dt

    DIFFERENTIAL EQUATIONS

    58. The differentiation equation

    21 ydy

    dx y

    = determines a family of circles with

    a) variable radii and a fixed centre (0, 1)

    b) variable radii and a fixed centre (0, -1)

    c) fixed radius 1 and a variable centres along the x-axis

    d) fixed radius 1 and variable centres along the y-axis. Ans. c

    59. Reasoning type

    Let a solution y=y(x) of the differential equation2

    x x 1 dy - 2y y 1 dx=0 satisfy y(2)= 2 / 3 .

    Statement 1: y(x) = sec(sec-1

    x - / 6 )

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    Statement 2: y(x) is given by1

    y=

    2 3

    x-

    2

    11

    x Ans. c