Question

how do I factor these:

1. x^3-3x^2-2x-6
2. x^3-3x^2+2x-6
3. 3x^3+9x^2+2x

Answer 1

You can do some trial and error here because of the simplicity of the factors.

1) try x=1 or as a (x-1) factor
2) try x=-1 or x+1 as a factor
3) try x=0 or x as a factor