Logic Exam Flashcards
Use logic to be logical
What does the symbol “ ^ “ mean
AND
What does the symbol “ v “ mean
OR
What does the symbol “ ¬ “ mean
NOT
What does the symbol “ —-> “ mean
IMPLIES
What does the symbol “ “ mean
IMPLIES (BOTH WAYS)
What does the symbol “ ∴ “ mean
Therefor
What does the symbol “ ≡ “ mean
Equivalent to
What is the first priority of the truth table
Parenthesis
What is the second priority of the truth table
Nots
What is the third priority of the truth table
Ands
What is the fourth priority of the truth table
Ors
How would you approach filling the truth table values for P if there are only 2 variables:
P alternates every 2 values.
ex: T T F F
How would you approach filling the truth table values for Q if there are only 2 variables
Q alternates every 1 value
ex: T F T F
How would you approach filling the truth table values for p if there are 3 variables
P alternates every 4 values
ex: T T T T F F F F
How would you approach filling the truth table values for q if there are 3 variables
Q alternates every 2 values
ex: T T F F T T F F
How would you approach filling the truth table values for r if there are 3 variables
R alternates every 1 values
ex: T F T F T F T F
How would you approach solving proofs
Start with most complicated side first
What do you do if you see an “ Or “
If there is one thing thats true then it is all true
What do you do if you see an “ And “
If there is one thing that is false then it is all false
What is a tautology
A formula that is true in every interpretation
What does “ Ǝ “ mean
At least one (there exists)
What does “ ∀ “ mean
For all (everyone)
Solve this:
~(~P) ≡
P
Solve this:
P v ~P ≡
True
Solve this:
P ^ ~P ≡
False
Solve this:
P v T ≡
True
Solve this:
P v F ≡
P
Solve this:
P ^ T ≡
P
Solve this:
P ^ F ≡
False
What is this law: (P v Q) ≡ Q v P
Commutative Law