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Really hard problem!!

$ \begin{align} xy&=-2 \\ xy^{a-1} &=-512 \\ x(y^a-1 ) &= 341y-341 \end{align} $

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    Did you want the third equation to be $x(y^a-1)=-341y-341$? The solution is much nicer then.2011-11-09

1 Answers 1

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From the first two (divide them) you get $y^{a-2}=256$.

So the third becomes $xy\cdot y \cdot 256 -x=341y-341$.

$-512 y-x=341y-341$. Plug $x=-2/y$ in this last equation you get a quadratic equation.

It is not really that hard problem. You just have to play a bit with it.