In the definition of Lebesgue measurability, I require for $E$ to be measurable that for any $\epsilon$, there is an open superset $A \supset E$ such that $m^*(A \setminus E) \leq \epsilon$.
Why require that $A$ is open? What would break otherwise?
2026-04-07 21:12:33.1775596353
Why require open supersets in definition of Lebesgue measurability
29 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in MEASURE-THEORY
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