How does one show that the set of infinitely differentiable functions compactly supported in a domain $\Omega\subset\mathbb{R}^n$ is not dense in $L^\infty(\Omega)$? Thanks!
2026-03-29 11:44:32.1774784672
Set of infinitely differentiable functions compactly supported in a domain of $\mathbb{R}^n$ not dense in $L^\infty$
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