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Probably pretty simple for ya'll but

  1. May 12, 2010 #1
    So I just got out of my intro to logic final at UMass and there was one question I just couldn't solve, and I'd like to know how. Anyways, here it is,

    1. ∀xFx V ∀xGx
    2. Show: ∀x(Fx V Gx)

    I did 90% of the exam in a half hour, then spent the next hour on this alone and couldn't really get that close. Anyways, just really curious how you'd go about doing it.

  2. jcsd
  3. May 12, 2010 #2
    Show how? By using the quantifier's semantic definitions or were you asked to use a particular proof system? Anyway, in the former, here's a hint: what must happen for the conclusion to be false?
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