Solve Integral 17(sin(x))^3(cos(x))^9

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Homework Statement



Integral 17(sin(x))^3(cos(x))^9

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Homework Equations


Integration


The Attempt at a Solution


I get (-17(5sin(x))^2 +1)(cos(x))^10)/60. But I'm wrong. It says I need to change something but I don't know what.
 
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substitute for cosx. then you will see that one of the sinx goes out with the change of integration variable. then you should be able to solve it easily
 
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