Solving Truth Tables & Writing WFFs with 2 Two-Place Connectives

AI Thread Summary
The discussion focuses on solving truth tables and writing well-formed formulas (wffs) using exactly two two-place connectives. Participants express confusion about creating wffs for given truth tables, particularly for wff a) and b). There is a debate on whether the negation operator "~" can be used, with some arguing that it is permissible since the instructions do not specify restrictions on one-place connectives. The algebraic approach to finding solutions is discussed, including the use of minterms and Karnaugh maps for graphical solutions. Overall, multiple valid solutions for the wffs are acknowledged, emphasizing the flexibility in logical expressions.
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I was given a truth table and I must write a wff with exactly two two-place connective. I am new to logic and don't know where to start. I need to find wff a), b), c) and d).

C B A ... wff a)
T T T ... T
T T F ... F
T F T ... T
T F F ... F
F T T ... T
F T F ... T
F F T ... T
F F F ... T

A B C ...wff b)
T T T ... F
T T F ... T
T F T ... F
T F F ... F
F T T ... F
F T F ... T
F F T ... F
F F F ... T

I have no clue on these first two. I tried many but they all seemed not to work.

A B ... wff c)
T T ... F
T F ... T
F T ... T
F F ... T

I think I can do this one:
this is equivalent to ~(A&B) but I need to use two two place connectives so I wrote ~(A&(B&B)) is this correct? Also the question didn't specify whether I can use "~". can I use it anyway?

A ... wff d)
T ... T
F ... T

This one I can also manage but I'm not sure what is the right answer. This is equivalen to (Av~A) which I can write as ((A&A)v~A). However, I can also write ((A&A)->A) or ((A&A)<->A) aswell. I think there's a few more which is right?
 
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The first step in the algebraic way is to write the minterm for the variables for each row where you see T as the outcome you leave all variables where the income is T as is, and negate those where the variable is F

for example
ABC
TFT = T
becomes
A\overline{B}C

For a graphical solution you can draw the Karnaugh table of the function, and try to cover the T's with some (possibly overlapping) rectangular areas. You come up with the solution in a similar way, just now you can drop inputs where they are both T and F in the rectangle.

I would say that the question did not say anything about one-place connectives, so using "~" should be okay.
You are right that there can be more solutions to such a problem.
I see no errors in your solutions above.
 
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