Solve the system of equations:
Solution
Consider the first equations of the system. It is easy to see that , and we
. It follows that all couples and without are solutions of the first equation. We are putting these solutions in the second equation. From this equation we have , and . Further, putting the first condition becomes . And we have solutions and but these couples don't satisfy the condition . Analogously putting the first condition becomes . Here we have solutions and which satisfy our conditions.
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