Calculate the Lebesgue measure of following sets:
- $A=\{(x,y): x\in\mathbb{Q} \vee y\in\mathbb{Q}\}$
- $B=\{(x,y): x-y\in\mathbb{Q}\}$
So I guess I need to calculate an integral over those sets. But I have no idea how to proceed?
2026-04-15 12:26:20.1776255980
Lebesgue measure of sets
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