SOLUTION: x-y=6 & xy=1 then x^3-y^3=?

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Question 765069: x-y=6 & xy=1 then x^3-y^3=?
Answer by ramkikk66(644) About Me  (Show Source):
You can put this solution on YOUR website!

Use the identity: %28x+-+y%29%5E3+=+x%5E3+-+y%5E3+-+3%2Ax%2Ay%2A%28x+-+y%29

Since we know x - y = 6 and xy = 1, substitute in the equation.

6%5E3+=+x%5E3+-+y%5E3+-+3%2A1%2A6

216+=+x%5E3+-+y%5E3+-+18

x%5E3+-+y%5E3+=+234

:)