![math prof on Twitter: "@SamuelGWalters I prove this theorem every time I teach real analysis. This is the problem (or one of) that got Cantor interested in set theory. He proved this math prof on Twitter: "@SamuelGWalters I prove this theorem every time I teach real analysis. This is the problem (or one of) that got Cantor interested in set theory. He proved this](https://pbs.twimg.com/media/EUTWHI_UUAAncDX.jpg)
math prof on Twitter: "@SamuelGWalters I prove this theorem every time I teach real analysis. This is the problem (or one of) that got Cantor interested in set theory. He proved this
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elementary set theory - Problem applying the Cantor-Bernstein Theorem proof technique to two open intervals. (Jech problem) - Mathematics Stack Exchange
![An Analysis of the First Proofs of the Heine-Borel Theorem - Borel's Proof | Mathematical Association of America An Analysis of the First Proofs of the Heine-Borel Theorem - Borel's Proof | Mathematical Association of America](https://www.maa.org/sites/default/files/images/upload_library/46/Heine-Borel_Theorem_Parker/Diagram1.jpg)
An Analysis of the First Proofs of the Heine-Borel Theorem - Borel's Proof | Mathematical Association of America
![Real Analysis, Lecture 13 Compactness and the Heine-Borel Theorem video lecture by Prof Francis Su of Other Providers Real Analysis, Lecture 13 Compactness and the Heine-Borel Theorem video lecture by Prof Francis Su of Other Providers](https://i.ytimg.com/vi/AQHVdiXRXQA/hqdefault.jpg)