Question(s) from Search: IIT

The sum if p > q is maximum when m is

a) 5

b) 10

c) 15

d) 20

At present a firm is manufacturing 2000 items. It is estimated that the rate of change of production P with respect to additional number of workers x is given by $\frac{\mathrm{dP}}{\mathrm{dx}}=100-12\sqrt{x}$

. If the firm employs 25 more workers then the new level of production of items is

a) 2500

b) 3000

c) 3500

d) 4500

If a, b, c; u, v, w are complex numbers representing the vertices of two triangles such that c = (1 − r)a + rb, w = (1 − r)u + rv where r is a complex number. The two triangles

a) have the same area

b) are similar

c) are congruent

d) none of these

Prove that

The question contains Statement – 1(assertion) and Statement – 2 (reason). Let f (x) = 2 + cosx for all real x.

Statement 1: For each real t, there exists a point c in [t, t + π] such that  because

Statement 2: f (t) = f[t, t + 2π] for each real t

a) Statement 1 and 2 are true. Statement 2 is a correct explanation of Statement 1.

b) Statement 1 and 2 are true. Statement 2 is not a correct explanation of Statement 1.

c) Statement 1 is true and Statement 2 is false.

d) Statement 1 is false. Statement 2 is true.

Let f(x) = (1 – x)² sin²x + x² and $g\left(x\right)=\underset{1}{\overset{x}{\int }}\left(\frac{2(t-1)}{t+1}-\mathrm{lnt}\right)f\left(t\right)\mathrm{dt}$

Which of the following is true?

a) g is increasing on (1, ∞)

b) g is decreasing on (1, ∞)

c) g is increasing on (1, 2) and decreasing on (2, ∞)

d) g is decreasing on (1, 2) and increasing on (2, ∞)

Use mathematical induction to prove: If n is an odd positive integer
then  is divisible by 24.

Given
 
 
Prove that
 

The coordinates of the in centre of the triangle that has the co ordinates of the mid points of its sides as (0, 1), (1, 1) and (1, 0) is

a) $2+\sqrt{2}$

b) $2-\sqrt{2}$

c) $1+\sqrt{2}$

d) $1-\sqrt{2}$

Using mathematical induction, prove that

 for n > 1

If f(x) =  then on the interval [0, π]

a) tan  and  are both continuous

b) tan  and  are both discontinuous

c) tan  and  are both continuous

d) tan  is continuous but  is not

One or more than one correct option

A ray of light along $x+\sqrt{3}y=\sqrt{3}$

gets reflected upon reaching X- axis, the equation of the reflected ray is

a) $y=x+\sqrt{3}$

b) $\sqrt{3}y=x-\sqrt{3}$

c) $y=\sqrt{3}x-\sqrt{3}$

d) $\sqrt{3}y=x-1$

If  and  where 0 < x ≤1, then in this interval

a) Both f (x) and g (x) are increasing functions

b) Both f (x) and g (x) are decreasing functions

c) f (x) is an increasing function

d) g (x) is an increasing function

The number of common tangents to the circles x² + y² – 4x − 6y – 12 = 0 and x² + y² + 6x + 18y + 26 = 0 is

a) 1

b) 2

c) 3

d) 4

Let p ≥ 3 be an integer and α, β be the roots of x² – (p + 1) x + 1 = 0. Using mathematical induction show that αⁿ + βⁿ
i) is an integer
ii) and is not divisible by p.

The function  is not differentiable at

a) – 1

b) 0

c) 1

d) 2

One or more than one correct option

Let RS be a diameter of the circle x² + y² = 1 where S is the point (1, 0). Let P be a variable point (other than R and S) on the circle and the tangents to the circle at S and P meet at the point Q. The normal to the circle at P intersect a line drawn through Q parallel to RS at a point E. Then the locus of E passes through the point(s)

a) $\left(\frac{1}{3},\frac{1}{\sqrt{3}}\right)$

b) $\left({\frac{1}{4},}^{}\frac{1}{2}\right)$

c) $\left(\frac{1}{3},-\frac{1}{3}\right)$

d) $\left(\frac{1}{4},-\frac{1}{2}\right)$

If x is not an integral multiple of 2π use mathematical induction to prove that
 

A circle passing through (1, −2) and touching the axis of X at (3, 0) also passes through the point

a) (−5, 2)

b) (2, −5)

c) (5, −2)

d) (−2, 5)

The circles  and  intersect each other in distinct points if

a) r < 2

b) r > 8

c) 2 < r < 8

d) 2 ≤ r ≤ 8

Prove by induction that
P_n = Aαⁿ + Bβⁿ for all n ≥ 1
Where α and β are roots of the quadratic equation
x² – (1 – P) x – P (1 – P) = 0,
P₁ = 1, P₂ = 1 – P², .  .  .,
P_n = (1 – P) P_{n – 1} + P (1 – P) P_{n – 2}  n ≥ 3,
and ,

Let P be a point on the parabola y² = 8x which is at a minimum distance from the centre C of the circle x² + (y + 6)² = 1. Then the equation of the circle passing through C and having its centre at P is

a) x² + y² – 4x + 8y + 12 = 0

b) x² + y² –x + 4y − 12 = 0

c) x² + y² –x + 2y − 24 = 0

d) x² + y² – 4x + 9y + 18 = 0

Let  then points where f (x) is not differentiable is (are)

a) 0

b) 1

c) ± 1

d) 0, ± 1

The slope of the line touching both parabolas y² = 4x and x² = −32y is

a) $\frac{1}{2}$

b) $\frac{3}{2}$

c) $\frac{1}{8}$

d) $\frac{2}{3}$

Let PQ and RS be tangents at the extremities of the diameter PR of a circle of radius r. If PS and QR intersect at a point x on the circumference of the circle, then 2r equals

a)

b)

c)

d)