Question(s) from Search: IIT

Prove that for complex numbers z and ω,   iff z = ω or .

The curve y = ax³ + bx² + cx + 5 touches the X – axis at (− 2, 0) and cuts the Y–axis at a point Q where the gradient is 3. Find a, b, c.

a)

b)

c)

d)

Points A, B, C lie on the parabola . The tangents to the parabola at A, B, C taken in pair intersect at the points P, Q, R. Determine the ratios of the areas of ΔABC and ΔPQR.

Consider the lines given by L₁ : x + 3y – 5 = 0; L₂ = 3x – ky – 1 = 0; L₃ = 5x + 2y −12 = 0. Match the statement/expressions in column 1 with column 2.

 is a circle inscribed in a square whose one vertex is . Find the remaining vertices.

a)

b)

c)

d)

Let a line passing through the fixed point (h, k) cut the X–axis at P and Y–axis at Q. Then find the minimum area of ΔOPQ.

a) hk

b) h²/k

c) k²/h

d) 2hk

Match the following

Let A_n be the area bounded by the curve y = (tanx)ⁿ and the line
x = 0, y = 0 and . Prove that for  . Hence deduce that
 

Consider the circle x² + y² = 9 and the parabola y² = 8x. They intersect P and Q in the first and fourth quadrants respectively. Tangents to the circle at P and Q intersect the X–axis at R and tangents to the parabola at P and Q intersect the X- axis at S. The radius of the incircle of △PQR is

a) 4

b) 3

c)

d) 2

ABCD is a rhombus. The diagonals AC and BD intersect at the point M and satisfy BD = 2AC. If the points D and M represent the complex numbers 1 + i and (2 – i) respectively then find the complex number x + iy represented by A.

a)  

b)  

c)  

d)  

Find all possible values of b > 0, so that the area of the bounded region enclosed between the parabolas  and  is maximum.

a) b = 1

b) b ≥ 1

c) b ≤ 1

d) 0 < b < 1

Let f(x) = sinx and g(x) = ln|x|. If the ranges of the composition function fog and gof are R₁ and R₂ respectively then

a)

b) ,

c)

d)

Let C₁ and C₂ be the graph of the function y = x² and y = 2x respectively. Let C₃ be the graph of the function
y = f (x), 0 ≤ x ≤ 1, f (0) = 0. Consider a point P on C₁. Let the lines through P, parallel to the axes meet C₂ and C₃ at Q and R respectively (see figure). If for every position of P (on C₁) the area of the shaded regions OPQ and OPR are equal, determine the function f(x).

a) x² – 1

b) x³ – 1

c) x³ – x²

d) 1 + x² + x³

A hemispherical tank of radius 2 meters is initially full of water and has an outlet of 12cm² cross section area at the bottom. The outlet is opened at some instant. The flow through the outlet is according to the law  where g(t) and h(t) are respectively the velocity of the flow through the outlet and the height of the water level above the outlet at the time t, and g is the acceleration due to gravity. Find the time it takes to empty the tank. (Hint: Form a differential equation by relating the decrease of water level to the outflow).

a)

b)

c)

d)

Let P be a point on the ellipse . Let the line parallel to Y–axis passing through P meets the circle  at the point Q such that P and Q are on the same side of the X–axis. For two positive real numbers r and s find the locus of the point R on PQ such that PˆR : RˆQ = r : s and P varies over the ellipse.

Find the area bounded by the curves
x² = y, x² = − y and y² = 4x – 3

a) 1

b) 3

c) 1/3

d) 1/9

Let E = {1, 2, 3, 4} and F = {1, 2}, then the number of onto functions from E to F is

a) 14

b) 16

c) 12

d) 8

For a twice differentiable function f(x), g(x) is defined as  If for a < b < c < d < e, f(a) = 0, f(b) = 2, f(c) = − 1, f(d) = 2, f(e) = 0 then find the maximum number of zeros of g(x).

a) 1

b) 2

c) 3

d) 6

Find the equation of the normal to the curve

A hyperbola having the transverse axis of length 2sinθ is confocal with the ellipse . Then its equation is

a)

b)

c)

d)

The angle between the pair of tangents from a point P to the parabola y² = 4ax is 45°. Show that the locus of the point P is a hyperbola.

The integral $\underset{0}{\overset{\pi }{\int }}\sqrt{1+4{\sin }^2\frac{x}{2}-4\sin \frac{x}{2}}\mathrm{dx}$

is equal to

a) $\pi -4$

b) $\frac{2\pi }{3}-4-4\sqrt{3}$

c) $4\sqrt{3}-4$

d) $4\sqrt{3}-4-\frac{\pi }{3}$

A box contains 24 identical balls of which 12 are white and 12 are black. The balls are drawn at random from the box one at a time with replacement. The probability that a white ball is drawn for the fourth time on the seventh draw is

a)

b)

c)

d)

Let F : ℝ → ℝ be a thrice differentiable function. Suppose that F(1) = 0, F(3) = −4 and F′(x) < 0 for all x ε (1, 3). Let f(x) = x F(x) for all x ε ℝ.The correct statement(s) is/are

a) f′(1) < 0

b) f(2) < 0

c) f′(x) ≠ 0 for every x ε (1, 3)

d) f′(x) = 0 for some x ε (1, 3)

Let A, B , C be three mutually independent events. Consider the two statements S₁ and S₂

S₁ : A and B ∪ Care independent

S₂  : A and B ∩ C are independent. Then

a) Both S₁ and S₂ are true

b) Only S₁ is true

c) Only S₂ is true

d) Neither S₁ nor S₂ is true