This would be a very handy lemma for me but I have been unable to prove it thus far.
If $S \in \mathbb{R}^n$ is bounded and is not of measure zero, then there exists a rectangle $R$ such that $S$ is dense in $R$.
Does anyone have any ideas on how to prove it? Can someone provide a counterexample?
Thank you! Brian
Edit: I should have clarified what I meant (moreover this may not be (or even worse, it could be completely different from) the standard definition of dense): $S$ is dense on $R$ if for every $x \in R$, if $\epsilon > 0$ then there exists $y \in S$: $|x-y| < \epsilon$.
Again thank you for the wealth of responses.
Maybe I'm misunderstanding the question, but it seems obviously wrong. A circle x^2 + y^2 <= 1 is obviously not dense in any rectangle.