Sign in
Please select an account to continue using cracku.in
↓ →
Join Our JEE Preparation Group
Prep with like-minded aspirants; Get access to free daily tests and study material.
The number of ordered triplets of the truth values of $$p, q$$ and $$r$$ such that the truth value of the statement $$p \vee q \wedge p \vee r \Rightarrow q \vee r$$ is True, is equal to _______
Correct Answer: 7
We need to find the number of ordered triplets $$(p, q, r)$$ of truth values such that $$p \vee (q \wedge (p \vee r)) \Rightarrow (q \vee r)$$ is True.
An implication $$A \Rightarrow B$$ is False only when $$A$$ is True and $$B$$ is False.
When is the consequent False?
$$q \vee r = F$$ requires $$q = F$$ and $$r = F$$.
With $$q = F, r = F$$, evaluate the antecedent:
$$p \vee (F \wedge (p \vee F)) = p \vee (F \wedge p) = p \vee F = p$$
So the implication is False only when $$p = T, q = F, r = F$$.
Total possible triplets = $$2^3 = 8$$. Number where implication is False = 1.
Number where implication is True = $$8 - 1 = 7$$.
Create a FREE account and get:
Predict your JEE Main percentile, rank & performance in seconds
Educational materials for JEE preparation
Ask our AI anything
AI can make mistakes. Please verify important information.
AI can make mistakes. Please verify important information.