# Proving an identity of Dirac's delta function

1. Nov 22, 2005

### Chen

Hello,

I need to prove (7) here:
http://mathworld.wolfram.com/DeltaFunction.html

The instructions were to start with the definition of the delta function by integral, and then chagne variables u -> g(x). But I couldn't get anywhere really.

Thanks,
Chen

2. Nov 22, 2005

Never mind.