How Do You Solve This Challenging Integral Involving Trigonometric Substitution?

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SUMMARY

The integral of the function x*√(2x-x²) can be solved using trigonometric substitution. The substitution x = 2sin²(u) transforms the integral into 16∫sin⁴(u)cos²(u) du. To proceed, completing the square under the square root is essential, specifically using the formula √(1-(1-x)²) for simplification. This approach streamlines the integration process and leads to a more manageable integral.

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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. [itex]\displaystyle{\sqrt{1-(1-x)^2}}[/itex] and then make the natural substitution.
 
edit: nvm
 
Last edited:

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