Answer
$-i$, $3+2i$ and $-2-i$
Work Step by Step
The Conjugate Pairs Theorem states that when a polynomial has real coefficients, then any complex zeros occur in conjugate pairs. This means that, when $(p +i \ q)$ is a zero of a polynomial function with a real number of the coefficients, then its conjugate $(p –i q)$, is also a zero of the function.
We can notice that the function has a degree of $6$, so it has $6$ complex including real zeros. Since $3$ real zeros are already mentioned in the statement, then we have $3$ zeros remaining. These zeros are: $-i$, $3+2i$ and $-2-i$, the conjugates of $i$, $3-2i$ and $-2+i$, by the Conjugate Pairs Theorem.