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Discrete math venn diagram proof

  1. Apr 23, 2008 #1
    Prove for all sets A,B, and C :
    A complement UNION B complement = (A intercept B) complement

    help me out here plz
  2. jcsd
  3. Apr 24, 2008 #2


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    If you (or your teacher) finds drawing Venn diagrams sufficient as a proof, you can just draw two Venn diagrams for the cases where A and B are disjoint or have an overlap and show that if you shade the left hand side or the right hand side, you will get the same shaded area. (I personally wouldn't consider that a real hard proof, however).
    Do you know how to indicate the different components in a Venn diagram (e.g. union, complement, etc)?
  4. Apr 24, 2008 #3
    this proof is to show why the two pictures/diagram are the same...
  5. Apr 24, 2008 #4


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    So, do you know how to draw Venn diagrams at all? Because if not, then the problem is not in the proof but in drawing the diagrams. And if you do, there is nothing to it, but drawing them.

    Also, you asked this question before, right?
  6. Apr 24, 2008 #5


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    You can also try googling DeMorgan's laws for more information.
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