How Do You Solve This Challenging Integral Involving Trigonometric Substitution?

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Homework Statement


integrate the following function: x*√(2x-x2)


Homework Equations


substitutions?


The Attempt at a Solution


I substituted x with x=2sin2u. From that I ended up with ∫x*√(2x-x2)= 16∫sin4u*cos2u

Now I'm supposed to use a formula from an integrals table.. but which?
 
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You should complete the square under the sqrt. \displaystyle{\sqrt{1-(1-x)^2}} and then make the natural substitution.
 
edit: nvm
 
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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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