Let A and B be sets and Let f:A---->B be a function. Define a function G: Power set (B)------->Power (A) by declaring that, for C is part of B or equal to B:(adsbygoogle = window.adsbygoogle || []).push({});

G(C)={x is element of A: f(x) is element of C}

Show that G is 1-1 if and only if f is onto.

Can anyone teach me this problem? Hopefully I can get some feelings about set theory. I just don't feel right.

Thank you so much for your good tips.

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# Homework Help: Can someone teach me this problem of sets.

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