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How do I refute or prove this?

  1. Sep 27, 2004 #1
    How do I refute or prove this???!!!!

    If f o g = (lambda)x.x, then f^-1 = g

    given that f:A -> B and g:B -> C
  2. jcsd
  3. Sep 27, 2004 #2
    i don't think i understand the problem. if f has an inverse, it would be f^-1: B->A; it wouldn't be that function g as defined.
  4. Sep 28, 2004 #3

    matt grime

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    once more, fog is not a function, monsu, the standard is to read from right to left when composing functions. and the first part of your question makes no sense to me. Pretend you don't know what the question is and read it as if for the first time.

    what is lambda, why is it in brackets, what is x, what is the dot between the xs? are you multiplying things? what's the input in fog (which isn't even a function?) is it a lambda or an x, or an x.x?
  5. Sep 28, 2004 #4
    You are right Matt, it isn't even a function... my brain seams to be damaging with work overload!! Thank you so much, once again!
  6. Sep 28, 2004 #5
    Thanks to you too fourier!!
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