Try It Now

Work these exercises to see how well you understand this material.

Answer: Let s = I will study, t = I will learn. The argument is: ((s → t) ∧ (¬t)) → (¬s) , call the argument a.

Since a is a tautology, the argument is valid.
Answer: In any true statement S, replace; ∧ with ∨, ∨ with ∧, 0 with 1, 1 with 0, ⇐ with ⇒, and ⇒ with ⇐. Leave all other connectives unchanged.