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.
Consider the statement "The match will be played only if the weather is good and ground is not wet". Select the correct negation from the following:
Let us translate every part of the given English sentence into symbolic logic so that each subsequent algebraic-style step is absolutely clear.
First, we introduce three simple statements:
$$P : \text{"The match will be played"}$$
$$Q : \text{"The weather is good"}$$
$$R : \text{"The ground is not wet"}$$
The original statement reads: “The match will be played only if the weather is good and the ground is not wet.” In propositional logic, the phrase “only if” is expressed by the implication arrow $$\rightarrow$$, with the condition coming after the arrow. Hence we write
$$P \;\rightarrow\; (Q \land R).$$
Our task is to find the negation of this entire implication. We start by recalling the standard logical equivalence for the negation of an implication:
Formula to be used: $$\neg(A \rightarrow B) \equiv A \land \neg B.$$
Here $$A$$ is $$P$$ and $$B$$ is $$(Q \land R)$$. Applying the formula gives
$$\neg\bigl(P \rightarrow (Q \land R)\bigr) \;=\; P \land \neg(Q \land R).$$
Now we still have the negation of a conjunction inside. We therefore invoke De Morgan’s law, which states
Formula to be used: $$\neg(X \land Y) \equiv \neg X \;\lor\; \neg Y.$$
Taking $$X = Q$$ and $$Y = R$$, De Morgan’s law yields
$$\neg(Q \land R) \;=\; \neg Q \;\lor\; \neg R.$$
Substituting this back into our earlier result, we obtain
$$\neg\bigl(P \rightarrow (Q \land R)\bigr) \;=\; P \land (\neg Q \lor \neg R).$$
Let us now translate this final symbolic form back into ordinary language:
• $$P$$ is true ⇒ “The match will be played.”
• $$\neg Q$$ is true ⇒ “The weather is not good.”
• $$\neg R$$ is true ⇒ “The ground is wet.”
So the entire expression $$P \land (\neg Q \lor \neg R)$$ becomes
“The match will be played and (the weather is not good or the ground is wet).”
Scanning the given options, we see that Option C states exactly this sentence:
“The match will be played and weather is not good or ground is wet.”
Hence, the correct answer is Option C.
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.