Ok so I was attempting to solve an integration by parts problem and somewhere along the line I got stuck. Here's the problem:(adsbygoogle = window.adsbygoogle || []).push({});

[tex] \int^{\infty}_{2} {x^2 e^{-x} - 2xe^{-x}[/tex]

After using integration by parts twice I came up with this:

[tex]2xe^{-x} - x^{2}e^{-x} + 2e^{-x} \vert^{\infty}_{2}[/tex]

But this differs greatly with what my book has to say. They came up with an answer around .5. Any ideas on this one?

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# Integration by parts problem

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