How Do You Solve This Challenging Integral Involving Trigonometric Substitution?

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The integral in question involves the function x*√(2x-x²), and the initial substitution made was x=2sin²(u). This led to the transformation of the integral into 16∫sin⁴(u)cos²(u). To proceed, it is suggested to complete the square under the square root and utilize a formula from an integrals table. The discussion highlights the importance of proper substitution techniques in solving challenging integrals. Ultimately, the focus remains on finding the right approach to simplify and evaluate the integral effectively.
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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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Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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