posted by Andrea .
How would you integrate tan5xdx ?
Thanks in advance.
Can you use u substitution?
try taking the derivative of
that should give you a good hint
I know you get -sin x; I know how to do the problem without the 5, but I don't understand how to do the problem since it is tangent of 5x
The derivative of ln(cosx) is actually
-tanx, not -sinx. "ln" means "natural (base e) logarithm of..
For the integral of tan 5x, let u = 5x
tan 5x = u
du = 5 dx
integral of tan(5x) dx
= integral of (1/5) tan u du
= -(1/5)ln cos u
= -(1/5)ln cos(5x)