The function f(x)=(x−1)|x−1|+sin(|x|) is
differentiable for all x∈R−{1}
discontinuous at x=1
differentiable for all x∈R−{0}
differentiable for all x
Functions in |x| is not differentiable at x=0 but x x is differentiable ∀x
Function (x−1)|x−1| is differentiable at all points. So, function f(x)=|x−1|(x−1)+sin|x| is not differentiable at x=0 only.