1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Set theory, functions, bijectivity

  1. Sep 5, 2009 #1
    f:X[tex]\rightarrow[/tex]Y, A[tex]\subset[/tex]X
    f(Ac)=[f(A)]c implies f bijective.

    Just trying to apply the definitions of injective and bijective. The equivalence makes sense but I am having a hard time showing it.

    f(x)=f(y) implies x=y and for every y in Y there exists a x in X s.t. f(x)=y.

    I mean all I have is if f(x)=f(y)
    then f(X\x)=Y\f(x\x)=f(X\y)-Y-f(X\y)...
     
    Last edited: Sep 5, 2009
  2. jcsd
  3. Sep 6, 2009 #2
    what's the question?
     
  4. Sep 8, 2009 #3
    this implication
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Set theory, functions, bijectivity
  1. Bijective function (Replies: 2)

Loading...