ok i have been studying the in-depth processes of trigonometric substitution with integrals and this problem has me frusterated.(adsbygoogle = window.adsbygoogle || []).push({});

[tex]\int x^2\sqrt{(x^2-4)} dx[/tex]

The evaluation is clear (from an oldTable of IntegralsI found), but the derivation is not at all clear, which is what i want to know.

I also tried to solve this by integration by parts, but every approach ended with an even more complicated integral, so trig substitution is probably the best choice.

Can anyone help?

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# Difficult integral for Trig Substitution

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