I'm reviewing some problems for a coming up test and was assigned some practice problems and wondering if you guys could say if you agree with my answers or not.(adsbygoogle = window.adsbygoogle || []).push({});

Given sets A and B does there exist a function s.t

[itex] \forall (b \in B) (|f^{-1}(\{b\})| < ∞)[/itex]

f: Z to R - No elements in R > Z, thus set B will always contain a subset that does not get mapped via the inverse function.

f: R to Z - No, there exists no inverse function that satisfies this

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# Does there exist a function s.t

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