If statement forms P and Q are logically equivalent, then P ↔ Q is a tautology. Conversely, if P ↔ Q is a tautology, then P and Q are logically equivalent. Use ↔ to convert each of the logical equivalences into a tautology. Then use a truth table to verify each tautology. a) p → (q ∨ r ) ≡ (p ∧ ∼ q) → r

Determine whether the logical statement is a tautology, a contradiction or neither: (p→q) → (p v q). [Hint: Use a truth table with 4 rows; you need to check the last row; all T is a tautology: all F is a contradition; a mixture of T and F is neither.] Example statement: If adopting new software leads to savings, then we'll either adopt new software or save money. The parentheses fit in the statement like this: If (adopting new software leads to savings), then (we'll either adopt new software or save money). This interpretation gives adopting new software leads to savings = If we adopt new software, then we'll save money O a. Tautology O b. Neither Oc. Contradiction

Check if ¬P is a logical consequence of:

For each logical argument, select all the truth assignments for the propositional variables that show the logical argument is invalid. 1) 2) r S T T r T F T F p+ -q rv ¬S FT F T :- F F F F