(adsbygoogle = window.adsbygoogle || []).push({}); [SOLVED] Dirac delta function

1. The problem statement, all variables and given/known data

Prove that [tex]\delta(cx)=\frac{1}{|c|}\delta(x)[/tex]

2. Relevant equations

3. The attempt at a solution

For any function f(x), [tex]

\int_{-\infty}^{\infty}f(x)\delta(cx) dx = \frac{1}{c}\int_{-\infty}^{\infty}f(t/c)\delta(t) dt

[/tex]

where I have used t=cx.

[tex]

=\frac{1}{c}f(0)

[/tex]

This is fine and matches RHS for c>0. But how do we get the mod sign for c<0. Why isn't the above procedure valid for c<0 as well?

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Dirac delta function proof help

**Physics Forums | Science Articles, Homework Help, Discussion**