- #1

- 22

- 0

## Homework Statement

I want to show that if the chhord length ||f(s)-f(t)|| depends only on |s-t| then the f is part of a line or circlle. f may not be regular or unit speed.

## Homework Equations

## The Attempt at a Solution

I'm trying to differentiete it and taking ||f'(t)||, but I really need help, because it's not working for me.