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Distributive property of Sets

  1. Nov 17, 2012 #1
    Hello all, while practicing set theory, I cam across this problem:

    If A and B are sets, prove that A x (B-C) = (AxB) - (BxC).

    This looks suspiciously like the distributive property but it's not. Is this simply a typo? Shouldn't the problem look like this:

    A x (B-C) = (AxB) - (AxC)

    Thanks for any suggestions.
  2. jcsd
  3. Nov 17, 2012 #2
    You can easily check and understand its a typo.
    Let A = {1,2},
    B = {3,4}
    C = {3}.
    AX(B-C) = (1,4) (2,4)
    AXB 1,4 2,4 1,3 2,3, and BXC = 3,3 4,3.
    I hope I'm not making a full of myself and your doing things that are much more complicated then what I just said :)

    Thanks, Bonaparte
  4. Nov 17, 2012 #3
    No, you're not making a fool of yourself. I think it's a typo too.
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