- #1
coaxmetal
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Homework Statement
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[tex]x\frac{d}{dx}\delta(x)=-\delta)(x)[/tex]
using the gaussian delta sequence ([tex]\delta_n[/tex]) and treating [tex]\delta(x)[/tex] and its derivative as in eq. 1.151.
Homework Equations
the gaussian delta sequence given in the book is
[tex]\delta_n=\frac{n}{\sqrt{\pi}}e^{-n^2x^2}[/tex]
and eq 1.151 is just part of the definition of the delta function:
[tex]f(0)=\displaystyle\int_{-\infty}^{\infty}f(x)\delta(x)dx[/tex]
The Attempt at a Solution
thus far, I have tried substitution the derivative of [tex]\delta_n(x)[/tex] for the derivative of the delta function, and then taking the limit as n goes to infinity, but that got me nowhere. I have also tried integrating both sides to see where it got me, but that was nowhere useful. The problem is I just don't understand how the derivative of the delta function works on its own.