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Topic: Logic Help
Replies: 1   Last Post: Jul 30, 1998 11:58 AM

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 Michael Thwaites Posts: 22 Registered: 12/6/04
Re: Logic Help
Posted: Jul 30, 1998 11:58 AM

Russell -

I would prove this by trying all the possible values of P and Q. There are
only Four combinations, T,T, T,F, F,T and F,F for P,Q. Evaluate the left
and right sides of each equation for each of the four cases and see if they
are equal.

Michael

>Can anyone help me prove the following three equivalences:
>
>(P or Q) and not(P and Q) = (P and notQ) or (Q and notP)
>
>P <---> Q = (P and Q) or (notP and notQ)
>
>(P ---> R) and (Q ---> R) = (P or Q) ---> R
>
>If you could email me with the proofs, I would very much appreciate it.
>
> -Russell (Russ256@aol.com)

Date Subject Author
7/30/98 Russ256
7/30/98 Michael Thwaites