JEE Main 2020MathematicsMatricesEasyMCQ

JEE Main 2020 — Matrices Question with Solution

JEE Main 2020 (09 Jan Shift 1)

Question

If A=1121341-13, B=adjA and C=3A, then adjBC is equal to

Choose an option

Show full solutionCorrect option: A
Correct answer
A8

Step-by-step explanation

A=1121341-13=9+4-13-4+2-1-3=13+1-8=6
adjB=adjadjA=An-12=A4=362
C=3A=33×6
adjBC=36×3633×6=8

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About this question

This is a previous-year question from JEE Main 2020, covering the Matrices 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.