Let $A$ and $B$ be two infinite sets. If I can show an injective function from $A$ to $B$ and another injective function from $B$ to $A$, can I then say that they have the same cardinality?
2026-03-30 00:04:43.1774829083
Cardinality of Infinite Sets using injections
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Yes, you can. This is known as the Cantor-Schröder-Bernstein theorem (apparently also sometimes Schröder-Bernstein theorem).