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Homework Help: A denumerable question

  1. Sep 26, 2010 #1
    1. The problem statement, all variables and given/known data

    Let S be the set of positive multiples of three which are greater than one hundred.
    Show that S is denumerable.


    2. Relevant equations



    3. The attempt at a solution
    let [tex]\phi[/tex]: [tex]N[/tex] [tex]\rightarrow[/tex] S
    be given by [tex]\phi[/tex](n)= 99+3n is a bijection
    thus it is denumerable

    can someone tell me if that is right? if not can you tell me what i did wrong?
     
  2. jcsd
  3. Sep 26, 2010 #2

    Dick

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    Why would you think it's not right? It is.
     
  4. Sep 26, 2010 #3
    well its the first time im taking an math class like this and im just not sure if im doing things right
     
  5. Sep 26, 2010 #4

    Dick

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    Well, you are doing it right.
     
  6. Sep 26, 2010 #5
    Thanks for the reassurance
     
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