JEE Main 2021MathematicsMathematical ReasoningLogical ConnectivesmediumMCQ

JEE Main 2021 — Mathematical Reasoning Question with Solution

From: JEE Main 2021 (Online) 26th February Evening Shift

Question

Let F1(A, B, C) = (A B) [C (A B)] A and
F2(A, B) = (A B) (B A) be two logical expressions. Then :

Choose an option

Show full solutionCorrect option: C
Correct answer
CF1 is not a tautology but F2 is a tautology

Step-by-step explanation

Truth table for F1 :
JEE Main 2021 (Online) 26th February Evening Shift Mathematics - Mathematical Reasoning Question 66 English Explanation 1 F1 is not a tautology.

Truth table for F2 :
JEE Main 2021 (Online) 26th February Evening Shift Mathematics - Mathematical Reasoning Question 66 English Explanation 2
F2 is a tautology.

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About this question

This is a previous-year question from JEE Main 2021, covering the Mathematical Reasoning chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.