Question

Another integration:
int ((1/(1+sin z + cos z))) dz

Answer 1

Hmm looks like we need weierstrass for this?

If you let
\[u=\tan(\frac{z}{2}) \\ \\ du=\frac{1}{2}\sec^2(\frac{z}{2})dz\]
At the same time using weierstrass subs you get
\[\Large \int\limits \frac{2}{ \left(\frac{2 u}{u^2+1}+\frac{1-u^2}{u^2+1}+1\right)\left(u^2+1\right)} \, du\]
Simplify
\[\int\limits \frac{1}{1+u} \, du\]
Solve

Answer 2

@.Sam. What is weierstrass

Answer 3

http://en.wikipedia.org/wiki/Weierstrass_substitution

Answer 4

thanks , never read that .