Limits Continuity And Differentiability Question 44

Question: If $ f(x)=| 1-x |, $ then the points where $ {{\sin }^{-1}}(f| x |) $ is non-differentiable are

Options:

A) $ { 0,1 } $

B) $ { 0,-1 } $

C) $ { 0,1,-1 } $

D) None of these

Show Answer

Answer:

Correct Answer: C

Solution:

Given that $ f(x)=| 1-x | $

$ \therefore f(| x |)= \begin{vmatrix} x-1, & x>1 \\ 1-x, & 0<x\le 1 \\ 1+x, & -1\le x\le 0 \\ -x-1, & x<-1 \\ \end{vmatrix} . $

Clearly, the domain of $ {{\sin }^{-1}}(f| x |) $ is $ [-2,2] $ .

Therefore, it is non-differentiable at the points $ {-1,0,1} $ .