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Stevecgz
Sep19-05, 03:19 AM
I'm attempting to find:
\int \cos^2x\tan^3x dx
I've tried substitution and integration by parts but I'm having no success. Can someone help me out on how I get this one started?

Steve

dextercioby
Sep19-05, 03:41 AM
It's no big deal.

\int \frac{\sin^{3}x}{\cos x} \ dx =\int \frac{\sin x \left(1-\cos^{2}x\right)}{\cos x} \ dx =\int \tan x \ dx -\int \sin x \ d\left(\sin x\right) = ...

Daniel.

Stevecgz
Sep19-05, 04:57 AM
Thanks dextercioby, I understand it now.

Steve