How do I factorise this cubic expression?

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The discussion centers on the challenge of factorizing the cubic expression x^3 + 3x^2y + 2xy^2 + 6y^3. The original poster, Mike, is familiar with quadratics but struggles with cubic expressions. A suggestion is made to test rational roots and to group terms for easier factorization. Specifically, it is recommended to group the first two terms and the last two terms, then factor out common elements. The conversation emphasizes using systematic approaches to simplify the factorization process.
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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:)
 
Try grouping the first two and last two terms together and factor each group. Then...
 
Factor x2 from the first two terms and 2y2 from the last two terms.
 
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