JEE Main 2020MathematicsMatricesMediumMCQ

JEE Main 2020 — Matrices Question with Solution

JEE Main 2020 (03 Sep Shift 2)

Question

Let A be a 3×3 matrix such that adjA=2-11-1021-2-1 and B=adjadjA. If |A|=λ and B-1⊤=μ, then the ordered pair λ, μ is equal to

Choose an option

Show full solutionCorrect option: A
Correct answer
A3, 181

Step-by-step explanation

adj A=A2=9

⇒A=±3=λ⇒λ=3

⇒B=adj A2=81

⇒B-1T=B-1=B-1=1B=181=μ

∴λ, μ=3, 181.

Practice this on the real CBT interface

Solve this JEE Main question (and the rest of the Matrices chapter) on PrepSharp's TCS iON-style CBT player — with timer, bookmarks and session analytics.

Solve interactively →

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.