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Subject: "proof"     Previous Topic | Next Topic
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Conferences The CTK Exchange College math Topic #681
Reading Topic #681
Dad
guest
May-31-08, 09:41 PM (EST)
 
"proof"
 
   Let A be a set and let D be the set of all bijections from A to itself. Define a relation ~ on D by f~g <==> ∃h∈ D such that h º f = g º h. Prove ~ is an equivalence relation


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alexbadmin
Charter Member
2231 posts
May-31-08, 09:55 PM (EST)
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1. "RE: proof"
In response to message #0
 
   Well, let's think. You have to show


  1. Reflexivity

    If 1 is the identity mapping then fº1 = 1ºf.


  2. Symmetry

    If there is an h s.t. fºh = hºg then since h is a bijection h-1 exists so that h-1ºf = gºh-1.


  3. Transitivity

    In the same vein



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johnterry900
Member since May-30-08
Jun-02-08, 07:10 PM (EST)
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2. "RE: proof"
In response to message #1
 
   will you explain this more?


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alexbadmin
Charter Member
2231 posts
Jun-02-08, 07:11 PM (EST)
Click to EMail alexb Click to send private message to alexb Click to view user profileClick to add this user to your buddy list  
3. "RE: proof"
In response to message #2
 
   You'll have to ask a more direct question.


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