I saw this on a website. Prove that if r and s are positive integers with(adsbygoogle = window.adsbygoogle || []).push({});

r > s and gcd(r,s)=1, then gcd(rs , r + s)= 1. I can think of two ways to show this. Using the Euclidean algorithm or by showing that 1 can be a linear combination of rs and r + s. Funny thing...I couldn't do either them. I'm ashamed of myself and now I'm looking for some answers...

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