what trouble are you having doing truth tables? the first table should look like this:
2. Construct the truth tables of the following compound formulas:
i) P => Q v R
ii) (P v Q) ^ (P => Q)
the second should look like this:
Now fill out the tables based on the rules you know for each logical expression
construct truth tables similar to how i did in the last problem. the column quoted in each question part should have all T values in them if you fill out the tables right.3. Use truth tables to show that the following formulas are always true:
i) P ^ Q <=> Q ^ P
ii) P ^ (Q v R) <=> (P ^ Q) v (P ^ R)
iii) ¬(P v Q) <=> ¬P ^ ¬Q
Let P(S) be the statement "S is guilty".4. An enormous amount of loot has been stolen from a store. The criminal (or criminals) took the heist away in the car. Three well known criminals A, B and C were brought to Scotland Yard for questioning. The following facts were ascertained:
a) No one other than A, B and C was involved in the robbery
b) C never pulls a job without using A (and possible others) as an accomplice
c) B does not know how to drive
Is A innocent or guilty?
[Hint: A way to answer this question is to rewrite the recorded facts using propositional logic, with basic statements of the form A is guilty, B is guilty, C is guilty, respectively. The next step wuld be to write down the truth tables for the formulas obtained. Keeping in mind that formulas representing facts are always true, you will then be able to deduce an answer tot he question.}
Then (a) says (is true)
That is, if B is guilty, either A or C must be guilty also, because B would need one of them to accompany him to drive.
You need to ascertain whether P(A) is always T given all these cases are true. You can do this via truth table.