Math Is Fun Forum

sologuitar

Member

Registered: 2022-09-19

Posts: 467

Factor By Grouping

Factor 3x^3 - x^2 +18x - 6 by grouping.

I will divide the four terms into two terms.

3x^3 - x^2...Group A

18x - 6...Group B

I will factor each group individually.

Group A factors out to be x^2(3x^2 - 1).
I see that 3x^2 - 1 can also be factored to be (3x - 1)(x + 1).

Group B factors out to be 6(3x - 1).

Putting it a together I get this:

x^2(3x - 1)(x + 1)6(3x - 1)

I think the final answer looks like this:

6x^2(3x - 1)(x + 1)

Is this right?

Bob

Administrator

Registered: 2010-06-20

Posts: 10,640

Re: Factor By Grouping

No because when multiplied out you'll get an x^4 term.

3x^3 - x^2 +18x - 6

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

sologuitar

Member

Registered: 2022-09-19

Posts: 467

Re: Factor By Grouping

No because when multiplied out you'll get an x^4 term.

3x^3 - x^2 +18x - 6

Bob

I often get the wrong answer when rushing through basic problems.