Can someone please help me integrate 1 - (cos x)^2 ?

Thanks!

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- Feb 5th 2007, 04:29 PMturtleintegration
Can someone please help me integrate 1 - (cos x)^2 ?

Thanks! - Feb 5th 2007, 04:33 PMThePerfectHacker
- Feb 5th 2007, 05:47 PMAlvinCY
There's nothing wrong with what TPH is doing :-),

I personally hate integration by parts. It's long and dreaful, personally:

$\displaystyle \int 1 - cos^2 x\,dx$

$\displaystyle =\int sin^2 x\,dx$, using double angle formula for cos2x,

$\displaystyle =\int \frac{1 - cos2x}{2}\,dx$

$\displaystyle =\int \frac{1}{2} - \frac{cos2x}{2}\,dx$

$\displaystyle =\frac{x}{2} - \frac{sin2x}{4} + C$

Tada!