Hey guys,

the task: Factor completely (that is, remove common factors first).

a)

x^3 +x^2 -12x

Could somebody please explain how I can factor completely and remove common factors first?

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- Oct 17th 2012, 07:17 PMford2008Factor completely
Hey guys,

the task: Factor completely (that is, remove common factors first).

a)

x^3 +x^2 -12x

Could somebody please explain how I can factor completely and remove common factors first? - Oct 17th 2012, 07:21 PMMarkFLRe: Factor completely
Observe that all terms have

*x*as a factor, so pull that out first, then you are left with a quadratic...to factor this you need two factors of -12 whose sum is 1. Can you finish? - Oct 17th 2012, 08:44 PMford2008Re: Factor completely
-3 times 4 = -12 and

the sum of -3+4 = 1 - Oct 17th 2012, 08:46 PMMarkFLRe: Factor completely
Yes, so what is the factored form of the given expression?

- Oct 18th 2012, 08:40 AMford2008Re: Factor completely
Factored form should be (x-3)(x+4) = x^2 +4x -3x -12 = x^2 +x -12 = x(x^2 +x -12) = x^3 +x^2 -12x

So the factored form should be just: x(x^2 +x -12) or not??? - Oct 18th 2012, 09:01 AMPlatoRe: Factor completely
- Oct 18th 2012, 09:34 AMford2008Re: Factor completely
2 other examples:

1.

2x^2 +4x -30

Common factor is 2

so 2(x-3)(x+5) is completely factored???

2.

3x^3 +21x^2 +36x

Common factor is 3x

so 3x(x+3)(x+4) is completely factored???