(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

do my professor did this in class, and it doesn't make sense to me

∫cos^5(x) sin^4(x) dx

∫cos^4(x) sin^4(x) cos(x) dx

∫(1-sin^2(x))^2 sin^4(x) cos(x) dx

∫(sin^4(x) -2sin^6(x) +sin^8(x))cos(x) dx

so the above I get but when my professor integrated I became lost, this is his solution

1/5 sin^5(x) - 2/7 sin^7(x) +1/9 sin^9(x)

shouldn't those sin be cos? And where did the cos on the outside go?

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# Trigonomic integrals

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