In propositional logic if (P → Q) ∧ (R → S) and (P ∧ R) are two premises such that
In propositional logic if (P → Q) ∧ (R → S) and (P ∧ R) are two premises such that
(P → Q) ∧ (R → S)
P ∨ R
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Y
Y is the premise :
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Correct answer: (D) Q ∨ S
Explanation
Given premises (P → Q) ∧ (R → S) and (P ∨ R). (P → Q) = ¬P ∨ Q and (R → S) = ¬R ∨ S. Resolving with P ∨ R, ¬P with P and ¬R with R resolve out, leaving the disjunction Q ∨ S (constructive dilemma). So Q ∨ S is correct.