Bijection between sets of functions

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Homework Help Overview

The discussion revolves around establishing a bijection between the sets of functions, specifically between (X x Y)^Z and X^Z x Y^Z, where X and Y are sets and Z is a set of indices. The participants are exploring the properties of functions and their mappings.

Discussion Character

  • Conceptual clarification, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants discuss the need for a function S that relates elements from (X x Y)^Z to X^Z x Y^Z. There are attempts to prove injectivity and surjectivity of a function psi, with some questioning the correctness of their reasoning regarding surjectivity.

Discussion Status

Some participants have made progress in proving injectivity and are seeking further hints for surjectivity. There are differing interpretations of the function psi and its properties, indicating an ongoing exploration of the topic.

Contextual Notes

Participants are working under the constraints of proving properties of functions without providing complete solutions, and there are references to attachments that may contain additional information relevant to the discussion.

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For two sets X and Y let X^Y be the set of functions from Y to X.

Prove that there is a bijection between (X x Y)^Z and X^Z x Y^Z.

Attempt: I could not get any further from that "there must be a function S with S(f)=g and S(f')=g for any g, f' in X^Z x Y^Z, and where f is in (X x Y)^Z."
 
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Thank you, I think I'm done with proving that psi is an injection but I can't prove that it's also a surjection. Could you give me another hint?
 
This is what I tried for surjectivity so far: psi is clearly a surjection, as for every ordered pair (h,g) there is an f such that psi(f)=(h,g), because when we look at the values of f, h and g at z we see that psi(x,y)=(x,y). But this is the identity function and therefore a surjection. Is that correct?
 
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define f(z)=(h(z),g(z)).verify that this is a counter image of (h,g)
 

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