Do there exist positive integers and such that
Solution
The given equation is equivalent to
The fifth power of any positive integer ends with the same digit as the number itself. Therefore, ends with the same digit as , which in turn ends with the same digit as . Since also ends with the same digit, the difference ends with zero. Similarly, the difference ends with zero. However, the sum of numbers ending in zero cannot end in four. Therefore, there are no integers that satisfy the given equation.
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