How Should Integral Limits Change When Substituting in Trigonometric Functions?

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Homework Statement


\int^{2\pi}_{0}cos^{2}(\theta)sin^{2}(\theta)cos(\theta)sin(\theta)d\theta
If I set x=cos^{2}(\theta), the integral limit should be from 1 to 0 or need I break this integral into to 4 parts (i.e from 1 to 0 plus from 0 to 1 plus from 1 to 0 plus from 0 to 1)?

Homework Equations





The Attempt at a Solution

 
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Do you know any trig identities that can be used to express

\cos(\theta) \sin(\theta)

in another way?
 
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