\begin{equation} \forall α \in I\; A_α \text{ is a compact set} \implies \bigcap \{ A_\alpha : \alpha \in I\} \text{ is a compact set} \end{equation}
How to prove this problem?
I know definition of compact, but I can't use it.
2026-04-24 07:40:45.1777016445
Prove compact set and index set
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