- #1

- 1,041

- 3

## Homework Statement

Prove that the function [tex]f(x)=\sqrt(1-\sqrt(1-x^2))[/tex] has a finite one sided derivative at the point x=0.

## Homework Equations

## The Attempt at a Solution

What the heck is a one sided derivative? If I differentiate it, and put limit x=0, I get infinity, which is definitely NOT finite!

Do I use the fundamental definition of a derivative here and put lim x=0- or something?