What's the derivative of ?
And then think about how you'd integrate with respect to x.
I am looking at a problem integrating sinh^5(x)cosh(x) dx. They set u=sinh so then du=cosh, then they get a final answer of sinh^6x/6. I am not understanding what happened to the coshx can some one please explain this to me?
that is what happened to the cosh(x), it was replaced by 1 when we changed the variable to u. so cosh(x)dx became du
So our integral becomes:
the rest follows.
taking the derivative of the answer by the chain rule gets us back to the original integrand, which should happen