JEE Main 2021 — Mathematical Reasoning Question with Solution
From: JEE Main 2021 (Online) 26th August Evening Shift
Question
Consider the two statements :
(S1) : (p q) ( q p) is a tautology .
(S2) : (p q) ( p q) is a fallacy.
Then :
(S1) : (p q) ( q p) is a tautology .
(S2) : (p q) ( p q) is a fallacy.
Then :
Choose an option
Show full solutionCorrect option: C
Correct answer
Cboth (S1) and (S2) are true.
Step-by-step explanation
S1 : ( p q) (q p) = (q p) (q p)
S1 = q ( p p) = qvt = t = tautology
S2 : (p q) ( p q) = (p q) (p q) = C = fallacy
S1 = q ( p p) = qvt = t = tautology
S2 : (p q) ( p q) = (p q) (p q) = C = fallacy
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