Which one of the following statements is not a tautology?
Question:

Which one of the following statements is not a tautology?

1. (1) $(p \vee q) \rightarrow(p \vee(\sim q))$

2. (2) $(p \wedge q) \rightarrow(\sim p) \vee q$

3. (3) $p \rightarrow(p \vee q)$

4. (4) $(p \wedge q) \rightarrow p$

Correct Option: 1

Solution:

By truth table :