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View Full Version : probably pretty simple for ya'll but...


kshan5
May12-10, 03:20 PM
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.

Thanks.

JSuarez
May12-10, 09:22 PM
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?