Integration Homework Help: Solving for the Relationship Between Two Integrals

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SUMMARY

The discussion focuses on solving the relationship between two integrals involving the Gaussian function. Specifically, it demonstrates that the integral from 0 to infinity of \(x^2 e^{-ax^2} dx\) equals \(\frac{1}{4} \sqrt{\frac{\pi}{a^3}}\), given that the integral from negative to positive infinity of \(e^{-ax^2} dx\) equals \(\sqrt{\frac{\pi}{a}}\). The solution involves using integration by parts twice and substituting the limits appropriately to derive the required relationship.

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Homework Statement


Given that:

The integral between infinity and -infinity of

e-ax^2 dx = [tex]\sqrt{\pi/a}[/tex]

show that

The integral between 0 and infinity of

x2.e-ax^2 dx = 1/4[tex]\sqrt{\pi/a^3}[/tex]


Homework Equations





The Attempt at a Solution



I have found the indefinite integrals of each, but cannot see how to show this relationship. Any help would be appreciated.
 
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Well, I assume you integrate by parts twice. Then anypart of your integral with the Gaussian, you simply substitute in your given value. any part that can you Plug in your actual limits of inf and -inf, you plug in those numbers.
 

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