Answer:
-k(k + 2)(k + 1)
Step-by-step explanation:
-k is a common factor here. Factoring -k out, we get:
-k(2 + k^2 + 3k), or (after writing the quadratic in standard form)
-k(k^2 + 3k + 2) = -k(k + 2)(k + 1)