Question

Factor a^3 - 3 + 3a^2 - a.

A) (a - 1)(a + 1)(a + 3)

B) (a^2 + 1)(a - 3)

C) (a^2 - 3)(a + 1

Answer 1

Reorder the numbers

a^3 -a +3a^2 -3
(a^3-a) + (3a^2-3)
a(a^2-1) +3(a^2-1)
(a+3)(a^2-1)
(a+3)(a+1)(a-1)