Practice Questions

Q70.A circle with centre (2, 3) and radius 4 intersects the line x + y = 3 at the points P and Q. If the tangents at P and Q intersect at the point S(α, β), then 4α −7β is equal to

Q71.Let the mean of the data x 1 3 5 7 9 Frequency (f) 4 24 28 α 8 be 5. If m and σ2 are respectively the mean deviation about the mean and the variance of the data, then 3α m+σ2 is equal to _______. JEE Main 2023 (13 Apr Shift 1) JEE Main Previous Year Paper

Q71.The ordinates of the points P and Q on the parabola with focus (3, 0) and directrix x = −3 are in the ratio β2 3 : 1 . If R(α, β) is the point of intersection of the tangents to the parabola at P and Q, then α is equal to

Q74.If the mean and variance of the frequency distribution xi 2 4 6 8 10 12 14 16 fi 4 4 α 15 8 β 4 5 are 9 and 15. 08 respectively, then the value of α2 + β2 −αβ is _____.

Q74.Let X = {11, 12, 13, … . , 40, 41} and Y = {61, 62, 63, . . . , 90, 91} be the two sets of observations. If x and y ¯are their respective means and σ2 is the variance of all the observations in X ∪Y, then x + y −σ2 is equal to ________

Q74.Let the mean and variance of 12 observations be 29 and 4 respectively. Later on, it was observed that two observations were considered as 9 and 10 instead of 7 and 14 respectively. If the correct variance is mn , where m and n are coprime, then m + n are coprime, then m + n is equal to (1) 315 (2) 316 (3) 314 (4) 317

Q74.The minimum number of elements that must be added to relation R = {(a, b), (b, c), (b, d)} on the set {a, b, c, d}, so that it is an equivalence relation is

Q74.Let the mean and variance of 8 numbers x, y, 10, 12, 6, 12, 4, 8 be 9 and 9. 25 respectively. If x > y, then 3x −2y is equal to _______

Q75.Let A = ⌊aˆiˆj⌋⋅aij prime number p ∈(2, 13) is _____ .

Q76.Let A be a n × n matrix such that |A| = 2 . If the determinant of the matrix Adj (2. Adj (2 A−1)) is 284 , then n is equal to _____ . Q77. ⎛ 2 10 8⎞ If a point P(α, β, γ) satisfying (α β γ ) 9 3 8 = (0 0 0) lies on the plane 2x + 4y + 3z = 5, then ⎝ 8 4 8⎠ 6α + 9β + 7γ is equal to (1) 5 (2) −1 4 (3) 11 (4) 115

Q76.If the sum of all the solutions of + cot−1( 1−x22x ) tan−1( 1−x22x ) = π3 , −1 < x < 1, x ≠0, is α − √34 , then α is equal to _____ .

Q78.Let f : R →R be a differentiable function that satisfies the relation f(x + y) = f(x) + f(y) −1, ∀ x, y ∈R. If f ′(0) = 2 , then |f(−2)| is equal to

Q78.For some a, b, c ∈N, let f(x) = ax −3 and g(x) = xb + c, x ∈R. If (fog)−1 (x) = ( 1 2 ) 3 , then (f ∘g)(ac) + (g ∘f)(b) is equal to _____ .

Q78.Let [x] be the greatest integer ≤x . Then the number of points in the interval (–2, 1) where the function f(x) = |[x]| + √x −[x] is discontinuous, is _____. sin2 x √3e is , x ∈(0, π2 ), is ke , then ( ke ) 8 + k8e5 + k8 sin x )

Q79.Let y(x) = (1 + x)(1 + x2)(1 + x4)(1 + x8)(1 + x16) . Then y′ −y′′ at x = −1 is equal to (1) 976 (2) 464 (3) 496 (4) 944

Q79.Let A = {1, 2, 3, 4, 5} and B = {1, 2, 3, 4, 5, 6} . Then the number of functions f : A →B satisfying f(1) + f(2) = f(4) −1 is equal to........ .Then and g(x) =

Q80.If ∫√sec 2x −1dx = α loge cos 2x + β + √cos 2x(1 ______.

Q80.The number of points, where the curve y = x5 −20x3 + 50x + 2 crosses the x-axis, is _____. x dx is equal to

Q80.Let I(x) = ∫√x+7x dx and I(9) = 12 + 7 loge 7. If I(1) = α + 7 loge(1 2√2), then α4 is equal to _____. dx = 3000k , then k is equal to _____.

Q80.Let k and m be positive real numbers such that the function f(x) = {3x2mx2+ k√x+ k2,+ 1, 0 <x ≥1x < 1 8f ′(8) is differentiable for all x > 0 . Then 1 is equal to f ′( 8 ) x dx is equal to

Q80.If aα is the greatest term in the sequence an = n3 , n = 1, 2, 3. . . . , then α is equal to ______ n4+147

Q81.The number of ways of giving 20 distinct oranges to 3 children such that each child gets at least one orange is _____ 1 15

Q81.If ∫0.15−0.15 100x2 −1

Q81.The number of words, with or without meaning, that can be formed using all the letters of the word ASSASSINATION so that the vowels occur together, is _____ .

Q81.If 𝑎 and 𝑏 are the roots of the equation 𝑥2 - 7𝑥- 1 = 0, then the value of 𝑎21 + 𝑏21 𝑎19 + 𝑏19