Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Continuity and Differentiability

Question:

The value of c in Rolle’s Theorem for the function f (x) = e x sinx, x∈ [π 0, ] is :

 

Options:

π/6

π/4

2π/3

3π/4

Correct Answer:

3π/4

Explanation:

By Rolle's Theorem : f'(c) = 0;

f'(x) = e x Sin x + e x Cos x

f'(x)|x=c = e x Sin x|x=c + e x Cos x|x=c

           0 = e x or 0 = (Sin x + Cos x)

          x  = 1, 3π/4