(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

{1/x+1/y / (x,y) in (IN*)^2} subset of ]0,2]

2. Relevant equations

3. The attempt at a solution

When x=y=1 u get a sum of 2 which is in ]0,2] and for any x and y greater than 1 u get a sum between 0<sum≤2.

It's a simple problem but i just don't know how to show the proof. Some help please.

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# Proof in set theory.

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