tandoorichicken
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How do you integrate even powers of trig functions, such as
[tex]\int\cos^{2}{\theta} \,d\theta[/tex]
[tex]\int\cos^{2}{\theta} \,d\theta[/tex]
Integrate Even Powers of Trig Functions: Cos²θ
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phy
Just an idea: perhaps you could break the integral into cos(theta)*cos(theta) and then integrate by parts from there 
relinquished™
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tandoorichciken, you must use an identity
[tex] <br /> cos^2 \theta = \frac{1 + cos 2\theta}{2}<br /> [/tex]
When the cosine function is raised to an even integer, say for example 4,
[tex] cos^4 \theta = (cos^2)^2 = (\frac{1 + cos 2\theta}{2})^2[/tex]
For the sine function, use the identity
[tex] <br /> sin^2 \theta = \frac{1 - cos 2\theta}{2}<br /> [/tex]
A word of Caution. When doing this method do not forget to double your angle ^_^
[tex] <br /> cos^2 \theta = \frac{1 + cos 2\theta}{2}<br /> [/tex]
When the cosine function is raised to an even integer, say for example 4,
[tex] cos^4 \theta = (cos^2)^2 = (\frac{1 + cos 2\theta}{2})^2[/tex]
For the sine function, use the identity
[tex] <br /> sin^2 \theta = \frac{1 - cos 2\theta}{2}<br /> [/tex]
A word of Caution. When doing this method do not forget to double your angle ^_^