Question from Cathrine, a student:

I am having trouble integrating this problem. It says to evaluate the integral but I don't know what to do or how to do it.

It is the integral of 13sin^3(x)*cos^7(x)dx

if you could help that would be awesome!

Hi Cathrine,

sin^{3}(x) = sin^{2}(x) sin(x) = (1 - cos^{2}(x)) sin(x) so the integrand can be written

13sin^3(x)*cos^7(x) = 13 (1 - cos^{2}(x)) cos^{7}(x) sin(x)

Does that help?

If you need further assistance write back, Harley