Math Help - need help with differenciable functions

describe three ways by which a function can fail to be differentiable

Originally Posted by bobby77

describe three ways by which a function can fail to be differentiable

1. It can have a step discontinuity.

2. It can have a corner then the derivative from the left is not equal to
the derivative from the right at the corner.

3. It can have a vertical asymptote where the derivative becomes arbitrary
large as we approach the asymptote.

RonL

Originally Posted by CaptainBlack

1. It can have a step discontinuity.

What is that?
Just saying discontinous at a point is good enough.