• question_answer The set of points where $f(x)={{(x-1)}^{2}}(x+|x-1|)$ is thrice differentiable, is A) $R$                            B) $R-\{0\}$C) $R-\{1\}$                   D) $R-\{0,\,\,1\}$

Since $|x|$ is not diff. at$x=0$ $\Rightarrow$$|x-1|$is not diff at$x=1$.${{x}^{n}}|x|$in$n$times diff. at$x=0$ $\Rightarrow$${{(x-1)}^{2}}|x-1|$is twice diff. at$x=1$but not thrice diff. at$x=1$