Question

Factor completely.
x3 + 6x2 - 4x - 24
(x + 6)(x - 2)(x + 2)
(x + 2)(x - 6)(x + 2)
(x - 6)(x + 2)(x + 2)

Answer 1

x^3 + 6x^2 - 4x - 24
Split it up into two groups.
(x^3 + 6x^2) + (-4x - 24)
Factor an x^2 out of first group and a -4 out of the second group.
x^2(x + 6) + -4(x + 6)
Factor an (x + 6) out of both sides.
(x^2 - 4)(x + 6)
Difference of squares.
(x + 2)(x - 2)(x + 6)

Answer is the first one.