Let $f(x)=\left\{\begin{matrix}(x-2)^2\sin\left(\frac{1}{x-2}\right)-|x|&,&x≠2\\-2&,&x=2\end{matrix}\right.$ then the points where f (x) is not differentiable are |
x = 0, 2 only x = 0 only x = 2 only none of these |
x = 0 only |
$f'(2)=\underset{h→0}{\lim}\frac{h^2\sin\frac{1}{h}-(2+h)+2}{h}$ Since $(x-2)^2\sin\left(\frac{1}{x-2}\right)$ is differentiable at x = 0 and |x| is not differentiable at x = 0 ∴ f (x) is not differentiable at x = 0 |