I feel really dumb for asking this, because I know it's something simple I'm just not seeing. Ok, given that(adsbygoogle = window.adsbygoogle || []).push({});

[tex]\int _{-\infty}^{\infty} e^{-x^2}dx = \sqrt{\pi } [/tex]

how to I find

[tex]\int _{-\infty}^{\infty} x^2e^{-x^2}dx = ? [/tex]

I have tried the substitution u=x^2, and integration by parts, but nothing is working. Any help? Thanks

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# Homework Help: Integration Problem

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