How do I solve the integral of cos^2(x) using trigonometric identities?

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To solve the integral of cos^2(x), use the trigonometric identity cos(2x) = 2cos^2(x) - 1 to rewrite cos^2(x) in terms of cos(2x). This transforms the integral into a more manageable form: ∫(1 + cos(2x))/2 dx. By integrating this expression, you can find the solution, which involves basic integration techniques. The final result will include both a constant and a term involving sin(2x). Understanding and applying trigonometric identities is crucial for solving such integrals.
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Could someone walk me through this one? I know what the answer is, but don't really see how that answer is come by. In the book, it just states the answer, so I guess its something obvious, but the answer still eludes me :(


Homework Equations


\int{Cos^2{(ax)}}dx
 
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Make sure you know your trig identities.

<br /> \cos 2x=2 \cos^2x-1<br />
 

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