How do you integrate int cos^3thetasqrt(sintheta)cos3θsinθ?

1 Answer
Oct 19, 2017

=2/3sin^(3/2)x-2/7sin^(7/2)x+C=23sin32x27sin72x+C

Explanation:

for thetaθ read xx

intcos^3xsin^(1/2)xdxcos3xsin12xdx

=intcosxcos^2xsin^(1/2 )xdx=cosxcos2xsin12xdx

=intcosx(1-sin^2x)sin^(1/2)xdx=cosx(1sin2x)sin12xdx

=intcosxsin^(1/2)x-cosxsin^(5/2)xdx=cosxsin12xcosxsin52xdx

by inspection

=2/3sin^(3/2)x-2/7sin^(7/2)x+C=23sin32x27sin72x+C

which can be simplified as required