Let $X$ be normed space.
How does compactness of any closed ball $\bar B(a,r)\; a \in X, r >0 \,$ relate to compactness of unit closed ball in $X$ ?
I have to prove in homework assignment that $\bar B(a,r)$ is compact iff $\bar B(0,1)$ is compact.
2026-03-27 23:36:02.1774654562
Compactness of closed unit ball $\bar B(0,1)$ in normed space
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