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wii
Feb26-11, 04:09 PM
I want to solve this equation

x^2 - 18 y^2 = 12

Any suggestion?

I thought , we have to find \sqrt 18and then find x/y

BUT I was confused and then stopped solving

Dickfore
Feb26-11, 04:14 PM
This equation has 2 unknowns. If you don't specify what set x and y are elements of, for example integer, it has an infinite set of solutions that can be represented parametrically as:


\begin{array}{l}
x = \pm 2 \sqrt{3} \, \cosh{t} \\

y = \frac{2 \sqrt{3}}{3} \, \sinh{t}
\end{array}

wii
Feb26-11, 04:18 PM
Sorry,
Both x & y are integers.

Buri
Mar2-11, 08:54 AM
You might get more help if you posted this in the Number Theory section...

Dickfore
Mar2-11, 09:37 PM
There is no solution.