Question

why the functions are not differentiable at the sharp points ?

Answer 1

Answer:

Step-by-step explanation:

The absolute value function is continuous (i.e. it has no gaps). It is differentiable everywhere except at the point x = 0, where it makes a sharp turn as it crosses the y-axis. A cusp on the graph of a continuous function. At zero, the function is continuous but not differentiable.