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by jimhefferon 665 days ago
This post is not about real numbers, though. It's about floating point numbers.
1 comments

Even if we were talking about real numbers (which we're not), it would still be true that (0, 1) and (1, +inf) have the same cardinality :)

As touched on in the post, 1/x is an explicit bijection (but any set of real numbers that contains an interval has the same cardinality)

But perhaps that's the interesting point — 1/x is *cannot be* an exact bijection for floating point numbers, because there's not a one-to-one mapping between the two sets.