Answer
$(y+2)(y-1)(y+1)$
Work Step by Step
$ y^{3}+2y^{2}-y-2\qquad$...factor in groups.
$=(y^{3}+2y^{2})+(-y-2)$
$=y^{2}(y+2)-1(y+2)\qquad$...factor out the common binomial factor,$y+2$.
$=(y+2)(y^{2}-1)\qquad$...recognize the difference of two squares: $a^{2}-b^{2}=(a-b)(a+b)$
$=(y+2)(y-1)(y+1)$
