Let $X$ be a compact and convex set and $f:X \to \mathbb{R}$ be a concave function. Therefore, $f$ is continuous on interior of $X$. I want to know whether $f$ is upper semi continuous on $X$. If not, under which (minimum) assumption is?
2026-02-23 20:17:21.1771877841
A concave function on a compact and convex set is upper semi continuous
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