x+y=xy=3

find x^3 + y^3

Anyone? Could really use some help on this the extra credit would be nice to have.

The work is more important than the answer, so any idea on how to get started so i could begin figuring it would be much appreciated.

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- December 9th 2008, 12:43 AMTwertzalgebra equations
x+y=xy=3

find x^3 + y^3

Anyone? Could really use some help on this the extra credit would be nice to have.

The work is more important than the answer, so any idea on how to get started so i could begin figuring it would be much appreciated. - December 9th 2008, 12:57 AMChop Suey
- December 9th 2008, 01:05 AMTwertz
ok i'm still stuck. it's Find x^3 + y^3 so am i trying to cube the original equation? a bit more of a boost maybe?

i've got to be taking it in the wrong direction

i cubed the original equation and moved everything so it was x^3 + y^3= -3x^2y-3xy^2-x^3y^3-27 - December 9th 2008, 01:20 AMChop Suey
- December 9th 2008, 01:24 AMnzmathman
You have

So

(since x+y = 3 and xy = 3 - December 9th 2008, 02:06 AMmr fantastic
- December 9th 2008, 03:24 AMCaptainBlack