(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Show that f : X ! Y is 1-1 and onto if and only if for each set A [itex]\subset[/itex] X, f(A^c) = [f(A)]^c. ......c is a complement ....

2. Relevant equations

proof by contradiction.

if f is not 1-1,there are x and y with f(x)=f(y)

3. The attempt at a solution

I was thinking if f is not onto ...then i can say A=X...BUT i can't figure it out..i can explain one to one or onto..i am just having hard time here.

[

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: One to one and onto

Can you offer guidance or do you also need help?

Draft saved
Draft deleted

**Physics Forums | Science Articles, Homework Help, Discussion**