How do I factorise this cubic expression?

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physicsfun_12
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Homework Statement


Hello there, hope you'r well.

I am having trouble factorising this cubic. I am comfortable with quadratics however I have never had to factorise anything to the power 3 before.

x^3+3x^2y+2xy^2+6y^3

Thanks in advance for any input.

Mike


Homework Equations


n/a


The Attempt at a Solution


I have had ago but didn't get very far!

(3x+2y)(xy) that does the bit in the middle, excluding the two terms to the power 3.

Thanks again for any help with this.

Mike
 
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physicsfun_12 said:
x^3+3x^2y+2xy^2+6y^3

Hi Mike! :smile:

(try using the X2 tag just above the Reply box :wink:)

Assuming it has rational roots, they must be x/y = ± 1 or 2 or 3 or 6, so just try all of them. :biggrin:

(to save time, do the "odd" terms together, and the "even" terms together :wink:)
 
Factor x2 from the first two terms and 2y2 from the last two terms.