GATE 2016 CS (CS2) – Question 11

Engineering Mathematics · Discrete Mathematics: Propositional and First Order Logic · 1 mark · Numerical answer

Consider (i) false, (ii) Q, (iii) true, (iv) $P\lor Q$, (v) $\neg Q\lor P$. How many are logically implied by $P\land(P\Rightarrow Q)$?

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Correct answer: 4.0 to 4.0

Explanation

The premise forces P true, then Q true by modus ponens. Expressions (ii), (iii), (iv) and (v) are therefore true in every model of the premise; false is not. Exactly 4 expressions are implied.

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