Why are functions of compact support so important? Is there any relation between functions of compact support and coproducts?
Olver, mentions that if $f$ is in some function space with domain $\Omega$, then $f+ \epsilon \eta$ is in the same function space, so long as $\eta$ is of compact support in $\Omega$. Why is that?
2026-02-22 19:50:49.1771789849
Why are functions of compact support so important?
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