Need help in completing this truth table.

P | Q | R | S | ~S | P^Q | R^S(the arrow goes down. cant find a down arrow)

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- Nov 7th 2009, 06:50 PMSiobhanTruth Tables
Need help in completing this truth table.

P | Q | R | S | ~S | P^Q | R^S(the arrow goes down. cant find a down arrow) - Nov 8th 2009, 06:50 AMVonNemo19
- Nov 8th 2009, 06:56 AMSiobhan
I really don't know if I have the correct wording on this. Please bare with me.

For example.

P Q R

T T T

T T F

T F T

T F F

F T T

F T F

F F T

F F F

Please try to encode what I've typed in the above post. If you know these it would be a great help.

Thank you for understanding,

Siobhan - Nov 8th 2009, 07:03 AMVonNemo19
I'm not the best with matrices in latex, but I'll try to help.

You've got the basic Idea. The number of lines needed will be 2 raised to the number of simple statements. Or

$\displaystyle L=2^n$

So you will need $\displaystyle 2^5=32$ lines if N is a simple statement, but I think by N, you may be trying to say "not"S, or $\displaystyle \sim{S}$. Is this correct. If so you will only need 16 lines. - Nov 8th 2009, 03:47 PMSiobhan
Updated. The N was a ~ LOL. My messy writing. Still need help with this though.

- Nov 8th 2009, 03:54 PMVonNemo19
- Nov 8th 2009, 04:07 PMSiobhan
Yup, correct

- Nov 8th 2009, 04:28 PMVonNemo19
Dude, I can't get the LaTex right, but

There will be 8 Ts and them 8 Fs under the P. Then The Ts and Fs will alternate by fours for the Qs. Then the Ts and Fs will alternate by 2s for the Rs, and by 1 for the Ss.

After you have written the 16 lines, change the truth values for the tildes. Then understand that a wedge is only false when both of its disjuncts are false. Then, look for a line in which all of the premises are true, but the conclusion is false, if this does not happen, the argument is valid.

Im sorry if this is vague. I will compute the truth table and get right back to you with the answer. Thanks for being patient with me. - Nov 8th 2009, 05:15 PMVonNemo19
argument appears to be valid.