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Compactness

General · Mathematics

Study notes

Q: Is (0,1) compact? Prove [0,1] is compact via Heine-Borel. (0,1): cover {(1/n,1)}: no finite subcover (0 escapes!): NOT compact! [0,1]: closed + bounded in ℝ: COMPACT (Heine-Borel!)! Every sequence has convergent subsequence! Continuous f: attains max/min (extreme value!)!

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