How Do You Integrate \(\cos^2(x) \tan^3(x) dx\)?

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To integrate \(\int \cos^2(x) \tan^3(x) \, dx\), the discussion highlights that substitution and integration by parts may not yield success. One suggested approach involves rewriting \(\tan^3(x)\) in terms of sine and cosine, leading to \(\int \frac{\sin^3(x)}{\cos(x)} \, dx\). This can be further simplified by separating the integral into two parts: \(\int \tan(x) \, dx\) and \(\int \sin(x) \, d(\sin(x))\). The conversation concludes with a participant expressing understanding of the method presented.
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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
 
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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.
 
Thanks dextercioby, I understand it now.

Steve
 
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