How do you integrate int cos^3xsinxdx?

2 Answers
Jan 23, 2017

int cos^3x sinx dx = - cos^4x/4+C

Explanation:

Note that:

-sinx dx = d(cosx)

so if you substitute u= cosx you have:

int cos^3x sinx dx = - int u^3 du = - u^4/4 +C = - cos^4x/4+C

Jan 23, 2017

Since d/dx(cos(x))=-sin(x)

then

intcos^3(x)sin(x)dx=-intcos^3(x)dcos(x)=-(cos^(4)(x))/4+C