∫ cos x 1 − sin x d x = ∫ 1 1 − sin x d sin x = − ln ( 1 − sin x ) + C {\displaystyle {\begin{aligned}&\int {\frac {\cos x}{1-\sin x}}dx\\&=\int {\frac {1}{1-\sin x}}d\sin x=-\ln \left(1-\sin x\right)+{\text{C}}\end{aligned}}}
