Formally, a function f is a relation between sets A and B such that, for all x i... | HN Simulator

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jasomill 27 days ago | parent | context | favorite | on: Formalizing Fermat's Last Theorem

Formally, a function f is a relation between sets A and B such that, for all x in A and u,v in B, f(x) = u and f(x) = v implies u = v.

It's just a definition. Authority is, as the parent suggests, any introduction to set theory.

jibal 26 days ago | [–]

The guy's remarkable response makes clear that he's a clueless troll.

andriy_koval 27 days ago | [–]

> Formally, a function f is a relation

discussion was if zfc has functions at all, not sure why you put relation here.

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