REVISION WORK IN CLASS XII : MATHEMATICS COMPILED BY M.SRINIVASAN, PGT(MATHS), ZIET, MUMBAI 1. If f(x) is an invertible function, find the inverse of ๐(๐ฅ) = 3๐ฅ−2 5 2. Let * be a binary operation defined by a*b = 3a + 4b - 2 find 4*5 5๐ฅ+3 3. If f(x) = 4๐ฅ−5, show that f๏ฏf is an identity function. 4. Show that the f:R๏ฎR defined by f(x) = |๐ฅ|is neither one-one nor onto. 5. * be a binary operation defined on Q, given by a *b = a + ab. Is * commutative. 6. Show that the relation defined on R by R = {(a, b) : a – b is divisible by 3: a , b ๏ Z} is an equivalence relation. 7. Show that the relation defined on R x R by (a ,b) R (c , d) ๏ a + b = b + c on the set N X N is an equivalence relation. 8. Show that f(x) = 7x – 5 is an invertible function. Find the inverse of f. 9. Consider f: R+ ๏ฎ [5 ๏ฅ) given by f(x) = 9x2 + 6x – 5, show that f is invertible. Also find f-1 10. Let * be a binary operation on NXN defined by (a , b) * (c , d) = (a+c , b+d). Show that * is commutative, associative. Find the identity element for * if exists. √3 11. Find the principal value of ๐ ๐๐−1 [ ] 2 1 12. Find the principal value of ๐๐๐ −1 (− 2) 13. Find the principal value of ๐ ๐๐−1 [๐ ๐๐ 3๐ ] 5 1−cos ๐ฅ 14. Simplify : ๐ก๐๐−1 √1+cos ๐ฅ 15. Show that : ๐ ๐๐−1 (2๐ฅ √1 − ๐ฅ 2 ) = 2 sin-1x 8 31 16. Solve for x : tan-1(x + 1) + tan-1(x – 1) = tan-1( ) 1 17. Prove that : 2 ๐ก๐๐−1 + ๐ก๐๐ −1 5 −1 ๐ฅ−1 18. Solve for x : ๐ก๐๐ + ๐ฅ−2 −1 3 19. Prove that : ๐ ๐๐ 20. Prove that : ๐ ๐๐ 5 −1 12 13 + ๐ก๐๐ 1 = ๐ก๐๐−1 8 −1 ๐ฅ+1 ๐ฅ+2 −1 8 ๐ ๐๐ = 17 −1 4 + ๐๐๐ 5 + = 4 7 ๐ 4 ๐ ๐๐−1 44 85 −1 63 ๐ก๐๐ 16 = ๐ ๐ฅ+3 4 5 4 )= ( ) find x and y. 21. If ( ๐ฆ−4 ๐ฅ+๐ฆ 3 9 2๐ฅ + 5 3 | = 0, find x. 22. If | 5๐ฅ + 2 9 23. Find the area of the triangle whose vertices are (3 , 1), (4.3) and (-5,4) 1 ๐ ๐+๐ 24. Using properties of determinants, prove that |1 ๐ ๐ + ๐ | = 0 1 ๐ ๐+๐ 25. If A and B are symmetric matrices, show that AB is symmetric, if AB = BA. 3 4 ), show thatA2 – 5A + 7 = 0 26. If A = ( −4 −3 REVISION WORK IN CLASS XII : MATHEMATICS COMPILED BY M.SRINIVASAN, PGT(MATHS), ZIET, MUMBAI ๐ ๐๐๐ฅ cos ๐๐ฅ sin ๐๐ฅ ) show by induction that An = ( ) for n๏N ๐๐๐ ๐ฅ − sin ๐๐ฅ cos ๐๐ฅ 6 1 −5 28. Express the matrix (−2 −5 4 ) as a sum of symmetric and skew-symmetric −3 3 −1 matrix. 27. Let A = ( cos ๐ฅ −๐ ๐๐๐ฅ 1 ๐ ๐2 29. Using properties of determinants: prove that |1 ๐ ๐ 2 | = (a – b) (b – c) (c – a) 1 ๐ ๐2 ๐ฅ ๐ฆ ๐ง 2 2 2 ๐ฅ ๐ฆ ๐ง 30. Using properties of determinants: prove that: | | = ๐ฅ๐ฆ๐ง (๐ฅ − ๐ฆ)(๐ฆ − ๐ง)(๐ง − ๐ฅ ) ๐ฅ3 ๐ฆ3 ๐ง3 31. Using matrices solve the system: 2 x – y = 4 ; 2y + z = 5 ; z + 2x = 7 1 −1 2 −2 0 1 32. Use the product (0 2 −3) ( 9 2 −3) to solve the system x – y + 2z = 1, 2y – 3z = 1, 3 −2 4 6 1 −2 3x – 2y + 4z = 2 33. Using matrices solve the system: x + y + z = 4 ; 2x – y + z = -1 ; 2x + y -3z = -9 1 2 2 34. If A = (2 1 2) prove that A2 – 4 A – 5I = 0. Hence fine A-1. 2 2 1 35. State the condition under which the following system has a unique solution, find the unique solution using matrix method. x + 2y – 2z + 5 = 0 , -x + 3y + 4 = 0, -2y + z – 4 = 0 36. If f(x) = 2๐ฅ+3๐ ๐๐๐ฅ 3๐ฅ+2๐ ๐๐๐ฅ is continuous at x = 0, find f(0) 2 37. Find the value of ‘k’ such that the function: ๐(๐ฅ) = { ๐(๐ฅ − 2๐ฅ) ๐ฅ < 0 is continuous at x = 0 cos ๐ฅ ๐ฅ≥0 ๐๐ฆ 38. Find ๐คโ๐๐ √๐ฅ + √๐ฆ = 5 at (4,9) ๐๐ฅ 39. Find the point on the curve y = x2 – 4x + 5 where the tangent to the curve is parallel to x – axis 40. Prove that f(x) = x3 + x2 + x + 1 does not have a maxima or minima 2๐ฅ − 1 ๐ฅ < 0 41. Discuss the continuity of : ๐(๐ฅ) = { 2๐ฅ + 1 ๐ฅ ๏ณ 0 ๐ฅ ๐ฅ๏น0 2|๐ฅ| 42. Examine the continuity of : ๐(๐ฅ) = {1 at x = 0 ๐ฅ=0 2 43. Determine the value of ‘k’ for which ๐(๐ฅ) = { ๐ 1−cos 4๐ฅ 8๐ฅ 2 ๐ฅ=0 ๐ฅ ๏น0 is continuous at x = 0 ๐๐ฅ 2 + ๐ 44. Determine the values of ‘a’ and ‘b’ such that the function: ๐(๐ฅ) = { 2 2๐๐ฅ − ๐ continuous. 1− ๐ ๐๐3 ๐ฅ 3๐๐๐ 2 ๐ฅ ๐ 45. Let f(x) = ๐(1−๐๐๐ ๐ฅ) (๐−2๐ฅ)2 { ๐ฅ< ๐ฅ= ๐ 2 ๐ 2 ๐ฅ> ๐ . Find a and b is f(x) is continuous at x = 2 ๐ 2 ๐ฅ>2 ๐ฅ = 2 is ๐ฅ<2 REVISION WORK IN CLASS XII : MATHEMATICS COMPILED BY M.SRINIVASAN, PGT(MATHS), ZIET, MUMBAI √1+๐ฅ− √1−๐ฅ 46. Find the derivative with respect to x : y = ๐ก๐๐−1 [ √1+๐ฅ+ √1−๐ฅ −1 47. Find the derivative with respect to x: y = (sin x)x + ๐ ๐๐ 48. If x = 2 cos๏ฑ - cos 2๏ฑ and y = 2 sin๏ฑ - sin 2๏ฑ, find 49. If ๐ฅ √1 + ๐ฆ + ๐ฆ √1 + ๐ฅ = 0 ๐๐๐๐ -1 2 ] √๐ฅ ๐๐ฆ ๐๐ฅ at ๐ = ๐ 2 ๐๐ฆ ๐๐ฅ 2 2 50. If y = (tan x) , prove that (1+x ) y2 + 2x (1 + x2) y1 = 0 51. Verify Rolle’s theorem if f(x) = x2 – 4x – 3 in the interval [1 4] 52. Find the points on the curve y = x3 – 2x2 –x at which the tangent lines are parallel to the line y = 3x – 2. 53. The volume of a spherical balloon is increasing at the rate of 25 cm3/sec. find the rate of change of it surface area at the instant when its radius is 5 cm. 54. Find the interval in which f(x) = x4 – 4x3 + 4x2 + 15 is increasing or decreasing. 55. Find the equation of the tangent and normal to the curve y = x2 + 4x + 1 at the point whose x coordinate is 3. 56. Evaluate: ∫ ๐ฅ+cos 6๐ฅ 57. Evaluate : ∫ 1 58. ∫0 ๐ฅ ๐๐ฅ 3๐ฅ 2 + ๐ ๐๐6๐ฅ ๐ฅ 2 ๐๐ฅ ๐๐ฅ ๐๐ฅ 1+๐ 2 1 ๐ฅ3 59. ∫−1 1+๐ฅ 2 ๐๐ฅ 60. Find the area of the region bounded by the parabola y = 4x2, the axis of y and the lines y = 1 and y = 4. ๐ฅ2 61. ๐ธ๐ฃ๐๐๐๐ข๐ก๐ โถ ∫ 2 ๐๐ฅ ๐ฅ −4๐ฅ+3 62. ๐ธ๐ฃ๐๐๐ข๐๐ก๐: ∫ log(1 + ๐ฅ 2 ) ๐๐ฅ 63. ๐ธ๐ฃ๐๐๐ข๐๐ก๐ โถ ∫ ๐ฅ 2 ๐ก๐๐−1 ๐ฅ ๐๐ฅ ๐ฅ 64. ๐ธ๐ฃ๐๐๐๐ข๐ก๐: ∫ ๐๐ฅ (๐ฅ+2)(3−2๐ฅ) 1−๐๐๐ 2๐ฅ 65. ๐ธ๐ฃ๐๐๐ข๐๐ก๐: ∫ ๐ก๐๐−1 √ ๐๐ฅ 1+๐ถ๐๐ 2๐ sin ๐ฅ 66. ๐ธ๐ฃ๐๐๐ข๐๐ก๐ โถ ∫ (1−cos ๐๐ฅ ๐ฅ)(2−cos ๐ฅ) ๐ 67. Evaluate: ∫0 ๐ฅ ๐๐ฅ 1+sin ๐ฅ 2 68. ๐ธ๐ฃ๐๐๐ข๐๐ก๐: ∫−2|2๐ฅ + 3| ๐๐ฅ ๐ ๐ฅ sin ๐ฅ 69. ๐ธ๐ฃ๐๐๐ข๐๐ก๐: ∫0 ๐๐ฅ 1+ ๐ถ๐๐ 2 ๐ 3 70. Evaluate : ∫1 (๐ฅ 2 + 3๐ฅ) ๐๐ฅ using limit of sums REVISION WORK IN CLASS XII : MATHEMATICS COMPILED BY M.SRINIVASAN, PGT(MATHS), ZIET, MUMBAI 71. Solve: ๐ ๐ ๐ ๐ ๐ − ๐๐ + √ ๐ − ๐๐ ๐ ๐ 72.Solve: (1 + x2) 73. Solve: (x – 1) ๐ ๐ ๐ ๐ ๐ ๐ ๐ ๐ ๐ ๐ 76. Solve: x 77. Solve: x = ๐ ๐ ๐ ๐ ๐ ๐ ๐ ๐ = ey = 2x3y 74. Solve: cos x cosy 75. Solve: =0 ๐ ๐ = sinx sin y, when y (1) = 2 ๐ ๐ ๐ ๐ ๐ ๐ฅ๐จ๐ ๐+๐๐ ๐ ๐๐จ๐ฌ ๐ = y (log y – log x + 1) ๐ = y – x tan ( ) ๐ 78. Solve: (y + x) ๐ ๐ ๐ ๐ =y–x 79. Solve: 2xy dy + (x2 + 2y2) dy = 0 80. Solve: (3xy + y2) dx + (x2 + xy) dy = 0 81. Solve: ๐ ๐ ๐ ๐ + ๐ ๐๐๐๐ = ๐ ๐๐จ๐ฌ ๐ 82. Solve: cos3x ๐ ๐ ๐ ๐ 83. Solve: (1 + x2) 84. Solve: 85. Solve: ๐ ๐ ๐ ๐ ๐๐ฆ ๐๐ฅ + y cosx = sin x ๐ ๐ ๐ ๐ + y = tan-1x − ๐๐ ๐๐๐๐ = ๐ฌ๐ข๐ง ๐๐ ๐๐๐๐๐ ๐๐๐๐ ๐ = ๐ ๐๐๐๐ ๐ = + 2๐ฆ = ๐ฅ ๐ ๐ ๐ 4๐ฅ 86. Find a unit vector in the direction of: ๐โ = 3๐ฬ − 2๐ฬ + 6๐ฬ 87. If ๐โ = ๐ฬ + 2๐ฬ − 3๐ฬ and ๐โ = 2๐ฬ + 4๐ฬ + 9๐ฬ , find a unit vector parallel to ๐โ + ๐โโ 88. For what values of ‘๏ฌ’ the following vectors ๐โ = 2๐ฬ + ๏ฌ๐ฬ + ๐ฬ and ๐โโ = ๐ฬ − 2๐ฬ + 3๐ฬ are perpendicular. โโโโโโ 89. If P(1, 5, 4) and Q(4, 1, 2) find the direction rations of ๐๐ 90. Find the projection of the vector ๐โ = 2๐ฬ + 3๐ฬ + ๐ฬ on ๐โโ = ๐ฬ − 2๐ฬ + 3๐ฬ 91. Find the direction cosines of a line parallel to 2๐ฅ−1 √3 = ๐ฆ+2 2 = ๐ง−3 3 92. Find the distance of the point (2 , 3 , 4) from the plane ๐โ๏ท (2 ๐ฬ + 3๐ฬ + ๐ฬ ) = 11 93. Find the equation of the line parallel to the vector (2 ๐ฬ + 3๐ฬ + ๐ฬ ) and passing through the point (-1, 1 ,1) in vector and Cartesian form. 94. Find the angle between the line ๐ฅ+2 4 = ๐ฆ−1 −5 = ๐ง 7 and the plane 3x – 2z + 4 = 0. 95. Find the direction cosines of the line normal to the plane 3x – y – 4z + 7 = 0.