• +91 9971497814
  • info@interviewmaterial.com

RD Chapter 30- Derivatives Ex-30.1 Interview Questions Answers

Question 1 : Find the derivative of f(x) = 3x at x = 2

Answer 1 :

Given:
f(x) = 3x
By using the derivative formula,

Question 2 :

Find the derivativeof f(x) = x2 – 2 at x = 10

Answer 2 :

Given:

f(x) = x2 – 2

By using the derivative formula,

= 0 + 20 = 20

Hence,

Derivative of f(x) = x2 –2 at x = 10 is 20

Question 3 : Find the derivative of f(x) = 99x at x = 100.

Answer 3 :

Given:
f(x) = 99x
By using the derivative formula,

Question 4 : Find the derivative of f(x) = x at x = 1

Answer 4 :

Given:
f(x) = x
By using the derivative formula,

Question 5 : Find the derivative of f(x) = cos x at x = 0

Answer 5 :

Solution:
Given:
f(x) = cos x
By using the derivative formula,

Question 6 : Find the derivative of f(x) = tan x at x = 0

Answer 6 :

Given:
f(x) = tan x
By using the derivative formula,

Question 7 :
Find the derivatives of the following functions at the indicated points:
(i) sin x at x = π/2
(ii) x at x = 1
(iii) 2 cos x at x = π/2
(iv) sin 2xat x = π/2

Answer 7 :

(i) sin x at x = π/2
Given:
f (x) = sin x
By using the derivative formula,

[Since it is ofindeterminate form. Let us try to evaluate the limit.]

We know that 1 – cos x = 2 sin2(x/2)

(ii) x at x = 1

Given:

f (x) = x

By using the derivative formula,

(iii) 2 cos x at x = π/2
Given:
f (x) = 2 cos x
By using the derivative formula,
(iv) sin 2xat x = π/2
Solution:
Given:
f (x) = sin 2x
By using the derivative formula,
[Since it is of indeterminate form. We shall apply sandwich theorem to evaluate the limit.]
Now, multiply numerator and denominator by 2, we get


Selected

 

RD Chapter 30- Derivatives Ex-30.1 Contributors

krishan

Share your email for latest updates

Name:
Email:

Our partners