Question

Factor completely.



-2k - k3 - 3k2



k(-k + 1)(k - 2)
-k(k - 1)(k - 2)
-k(k + 1)(k + 2)

Answer 1

What is the common factor of the three terms there?

Answer 2

k

Answer 3

Hmm.. One more.. Can you see the negative signs?

Answer 4

-k

Answer 5

is it the 2nd one

Answer 6

Yup!
So, take out the common factor and group the rest of the terms. You'll get this:
\[-2k - k^3 - 3k^2\]\[=-k(2+ k^2 + 3k)\]Rearrange the terms a bit:
\[ = -k (k^2+3k+2)\]
From this, we can see that the 2nd one is nowhere near to the answer.