Question(s) from Search: IIT

The sum  where  equals

a) i

b) i – 1

c) – i

d) 0

If f(x) is a continuous function defined for 1 ≤ x ≤ 3. If f(x) takes rational values for all x and f(2) = 10 then f(1.5) = .  .  .  .

a) 2

b) 5

c) 10

d) 20

If x, y, z are real and distinct then  is always

a) Non – negative

b) Non – positive

c) Zero

d) None of these

Match the following
Let [x] denote the greatest integer less than or equal to x

a) (i)→ A, B, C, (ii)→ A, D, (iii)→ C, D, (iv)→ A, B

b) (i)→ A, (ii)→ A, (iii)→ C, (iv)→ B

c) (i)→ B, (ii)→ D, (iii)→ C, (iv)→ A

d) (i)→ A, B, (ii)→ A, D, (iii)→ C, D, (iv)→ B

(One or more than one correct answer)
If  are complex numbers such that  and  then the pair of complex numbers  and  satisfy

a)

b)

c)

d) None of these

Express  in the form A + iB

a)

b)

c)

d)

Let = 10 + 6i and  . If z is a complex number such that argument of  is  then prove that  .

(Multiple choices)
The value of θ lying between θ = 0 and θ =  and satisfying the equation
 = 0 are

a)

b)

c)

d)

Let a complex number α, α ≠ 1, be root of the equation  where p and q are distinct primes. Show that either  or , but not together.

True/False
For the complex numbers  and  we write  and  then for all complex numbers z with  we have  . 

a) True

b) False

Find the area of the region bounded by the curves y = x², y = |2 – x²| and y = 2 which lies to the right of the line x = 1.

a)

b)

c)

d)

Let f : ℝ → ℝ be any function. Define g : ℝ → ℝ by g(x) = |f(x)| for all x. Then g is

a) Onto if f is onto

b) One–one if f is one–one

c) Continuous if f is continuous

d) Differentiable if f is differentiable

f(x) is a differentiable function and g(x) is a double differentiable function such that  
If  prove that there exists some c ε (−3, 3) such that .

If (x – r) is a factor of the polynomial f(x) = a_nxⁿ + .  .  . + a₀, repeated m times (1 < m ≤ n) then r is a root of  repeated m times.

a) True

b) False

A function f : ℝ → ℝ, where ℝ is the set of real numbers, is defined by . Find the interval of values of α for which f is onto. Is the function one to one for α= 3? Justify your answer.

Let f and g be real valued functions on (−1, 1) such that g’(x) is continuous, g(0) ≠ 0, g’(0) = 0, g’’(0) ≠ 0 and f(x) = g(x)sinx
Statement 1 -
Statement 2 – f’(0) = g(0)

a) Statement 1 is true. Statement 2 is true. Statement 2 is a correct explanation of statement 1

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

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

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

Differentiate from first principles (or ab initio)

a) 2xcos(x² + 1)

b) xcos(x² + 1)

c) 2cosx(x² + 1)

d) 2xcosx(x² + 1) + sin(x² + 1)

Let a + b = 4 where a < 2 and let g(x) be a differentiable function. If  for all x, prove that  increases as (b – a) increases.

A and B are two separate reservoirs of water. Capacity of reservoir A is double the capacity of reservoir B. Both the reservoirs are filled completely with water, their inlets are closed and then water is released simultaneously from both the reservoirs. The rate of flow of water out of each reservoir at any instant of time is proportionate to the quantity of water in the reservoir at the time. One hour after the water is released the quantity of water in reservoir A is   times the quantity of water in reservoir B. After how many hours do both the reservoirs have the same quantity of water?

a)

b)

c) ln2

d)  

The area of the quadrilateral formed by the tangents at the end points of latus rectum to the ellipse  is

a)  square units

b)

c)  square units

d) 27 square units

Let b ≠ 0 and j = 0, 1, 2, .  .  . , n. Let S_j be the area of the region bounded by Y–axis and the curve
.

Show that S₀, S₁, S₂, .  .  .  , S_n are in geometric progression. Also find the sum for a = − 1 and b = π.

a)

b)

c)

d)

A tangent to the ellipse x² + 4y² = 4 meets the ellipse x² + 2y² = 6 at P and Q. Prove that tangents at P and Q of the ellipse x² + 2y² = 6 are at right angles.

Let U₁ = 1, U₂ = 1, U_{n + 2} = U_{n + 1} + U_n, n > 1. Use mathematical induction to show that
 
for all integers n > 1

Given
 
 
Prove that
 

Each of the following four inequalities given below define a region in the XY–plane. One of these four regions does not have the following property: For any two points (x₁, y₁) and (x₂, y₂) in the region, point  is also in the region. The inequality defining the region that does not have this property is

a) x² + 2y² ≤ 1

b) max (|x|, |y|) ≤ 1

c) x² – y² ≥ 1

d) y² – x ≤ 0