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Homework Help: Discrete maths functions help

  1. Oct 24, 2011 #1
    Hi all I was wondering if you could help me with this problem:

    [PLAIN]http://img713.imageshack.us/img713/4306/giflatexl.gif [Broken]

    Could someone explain this relationship in plain english for me please?

    [PLAIN]http://img9.imageshack.us/img9/338/codecogseqno.gif [Broken]

    This is what I was thinking, but I think it is wrong:

    frogs(f) is a set of frogs where f is an element within the set F. Therefore frogs(toadie) is a set where toadie is an element of F. Therefore frogs(frogs(toadie)) means the set {toadie} is an element of F?
    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Oct 24, 2011 #2


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    You lost me with the first sentence. Seems to me if F is a set of frogs and f ε F, then f is a frog. So "the set of frogs of f" doesn't make sense to me.

    Not being set theory expert, I may be missing something.
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