
#1
Sep1808, 10:27 PM

P: 308

How do we prove in propositional calculus :
......p^(qvr) <===> (p^q)v(p^r) semantically and syntactically 



#2
Sep1908, 09:47 AM

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Well, what have you already come up with?




#3
Sep1908, 09:50 AM

Math
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Thanks
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P: 38,900

Comparing truth tables will do it quickly and neatly. Are you not allowed to use that method?




#4
Sep1908, 09:54 AM

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proof of p^(qvr) <==> (p^q)v(p^r)
I had to Google as well, as far as I can see, using truth tables would be the semantic proof.




#5
Sep1908, 12:54 PM

P: 308

Semantical proof without using true tables ,i have one in mind but i am not very positive about it.Then syntactically how about a contradiction you think it could work ,although it looks a bit messy




#6
Sep2008, 03:45 AM

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P: 4,301

It is not quite clear to me what you mean by a semantical proof, and a syntactical one.
Also, if you would post your idea we can have a look at it. Maybe you are on the right track but just need a last push, or maybe you even got it right but lack the confidence 


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