I'm having a hard time proving that $R_2$ with the standard topology is normal. I started off by trying to show that for any two disjoint closed sets, A and B, we could find balls (so since we're in $R_2$ open sets) around them, U and V, but I don't know how to guarantee that these two balls are disjoint from each other. Any hints would be appreciated!
2026-05-16 13:43:08.1778938988
Proving that $R_2$ with the standard topology is normal?
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