question_answer

The number of points where the function f(x) = max\[\{|\tan x|,\cos |x|\}\]is non-differentiable in the interval \[(-\pi ,\pi )\]are

A)  4                                            

B)  6

C)  3                                            

D)  2

Correct Answer: A

Solution :

Discontinuous at\[\pm \frac{\pi }{2}\]and sharp corner at \[x=\alpha \]and\[\beta .\] Hence, non-derivable at 4 points.