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??

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Irrational Number and the Borel Sets

**Physics Forums | Science Articles, Homework Help, Discussion**