One-sided derivative at one point.

- For

The absolute value function is differentiable on the left at 0 and .

- For

The absolute value function is differentiable on the right at 0 and .

- is differentiable on the left at 0;
- is differentiable on the right at 0;
- .

- For

The function is differentiable on the left at 0 and . - For

The function is differentiable on the right at 0 and .

Noah Dana-Picard 2007-12-28