Question:
Let $f(x)=\left\{\begin{array}{ll}(2+x), & \text { if } x \geq 0 ; \\ (2-x), & \text { if } x<0\end{array}\right.$ Show that $f(x)$ is not derivable at $x=0$
Solution:
Given function $f(x)=\left\{\begin{array}{l}(2+x), \text { if } x \geq 0 \\ (2-x), \text { if } x<0\end{array}\right.$
