Answer
$-2, -3\pm2i$
Work Step by Step
Step 1. Since $-2$ is a zero, use synthetic division as shown in the figure, we have $\frac{f(x)}{x+2}=x^2+6x+13$
Step 2. The other zeros can be found as $x=\frac{-6\pm\sqrt {6^2-4(13)}}{2}=\frac{-6\pm4i}{2}=-3\pm2i$
Step 3. We have all the zeros as $-2, -3\pm2i$
