Answer
$$\frac{1}{9}\cos(4-9x)+C$$
Work Step by Step
Finding the general antiderivative of $f$:
$\int{f(x)}dx$
$=\int\sin(4-9x)dx$
Given $$\int\sin({kx})dx=-\frac{1}{k}\cos({kx})+C$$
$\int\sin(4-9x)dx$
$=-\frac{1}{-9}\cos(4-9x)$
$=\frac{1}{9}\cos(4-9x)+C$