How do you find the integral of int [cot^5 (x) (sin^4(x) dx]?

1 Answer
Oct 7, 2015

I=ln|sinx|-sin^2x+sin^4x/4+C

Explanation:

int cot^5xsin^4xdx=int (cos^5x)/(sin^5x)sin^4xdx=

int (cos^4xcosx)/(sinx)dx=int ((1-sin^2x)^2cosx)/sinx dx=I

sinx=t => cosxdx=dt

I=int (1-t^2)^2/tdt=int (1-2t^2+t^4)/tdt=int (1/t-2t+t^3)dt

I=ln|t|-t^2+t^4/4+C

I=ln|sinx|-sin^2x+sin^4x/4+C