Answer
$y=\frac{1}{c-\cos x}$
Work Step by Step
$\frac{dy}{dx}+y^2\sin(x)=0$
Separate variables:
$\frac{dy}{dx}=-y^2\sin(x)$
$\frac{dy}{y^2}=-\sin(x)dx$
Integrate:
$-\int{\sin(x)dx}=\int{y^{-2}dy}$
$\cos(x)=-\frac{1}{y}+c$
$\frac{1}{y}=c-\cos x$
$y=\frac{1}{c-\cos x}$