Answer
-1 (with multiplicty 2), 1, and 2
Work Step by Step
Equate each unique factor to zero, then solve each equation:
$x+1=0 \text{ or } x-1=0 \text{ or } x-2=0
\\x=-1 \text{ or } x = 1 \text{ or } x=2$.
The factor $x+1$ appears twice so the zero -1 has multiplicity 2.