Then you should post the whole question, show what you've done, say where your stuck and then state that you want only a hint rather than the whole solution.

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There are two things you should never try to prove: the impossible and the obvious.

The greater danger for most of us lies not in setting our aim too high and falling short; but in setting our aim too low and achieving our mark. (Michelangelo Buonarroti)

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