Took a test in my Analysis class today. One question asked us to prove that the set of Irrational numbers was a Borel Set. After working on the other problems for 90 minutes, I stared blankly at this one for what seemed life a long time. I eventually showed (I think) that the set of Rational numbers is a Borel Set, and therefore, its complement is also.(adsbygoogle = window.adsbygoogle || []).push({});

Is there an easier was to do this??

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# Irrational Number and the Borel Sets

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