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## #1 2012-11-28 21:07:15

deiv
Guest

### factoring polynomials

Pls factor completely: (m^9)-(3•m^3)-2
tnx....

## #2 2012-11-28 22:41:01

bob bundy
Moderator

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### Re: factoring polynomials

hi deiv

Welcome to the forum.

You can simplify the problem by making the substitution

Then it becomes

I notice that x = -1 makes this expression zero, so by the factor theorem (x + 1) is a factor.

From there you can easily get the quadratic that goes with this and you'll find the formula will give another two factors.

Then you can go back to the m expression from there.

Bob

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

## #3 2012-11-28 23:19:05

bobbym

Online

### Re: factoring polynomials

Hi;

Or take it over to Wolfram.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #4 2012-11-28 23:34:45

deiv
Guest

### Re: factoring polynomials

3x(x+2y) + 4y(3x+2y)

## #5 2012-11-28 23:55:10

bob bundy
Moderator

Offline

### Re: factoring polynomials

What do you get if you multiply out the brackets and simplfy?

Bob

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

## #6 2012-11-29 00:30:59

bobbym

Online

### Re: factoring polynomials

I think you are going to find that is irreducible in Q and therefore in Z.

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.