Get Answers to all your Questions

header-bg qa

Among the statements :

(S 1)((p \vee q) \Rightarrow r) \Leftrightarrow(p \Rightarrow r)

(S 2)((p \vee q) \Rightarrow r) \Leftrightarrow((p \Rightarrow r) V(q \Rightarrow r))

 

Option: 1

only (S2) is a tautology


Option: 2

only (S1) is a tautology


Option: 3

neither ( S1) nor (S2) is a tautology


Option: 4

both (S1) and (S2) are tautologies


Answers (1)

best_answer

\begin{aligned} & S_1:((p \vee q) \Rightarrow r) \Leftrightarrow(p \Rightarrow r) \\ & p \quad q \quad r \quad \begin{array}{l} (p \vee q) \Rightarrow r \\ (\sim p \wedge \sim q) \vee r \end{array} \sim p \vee r \quad((p \vee q) \Rightarrow r) \Leftrightarrow(p \Rightarrow r) \end{aligned}

S_{1} is not a tautology 

S_2=((p \vee q) \Rightarrow r) \Leftrightarrow((p \Rightarrow r) \vee(q \Rightarrow r))

S_2 is not a tautology
So, neither S_1 nor S_2 is a tautology.

Posted by

sudhir.kumar

View full answer

JEE Main high-scoring chapters and topics

Study 40% syllabus and score up to 100% marks in JEE