JEE Main 2024 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 6 April 2024, Shift 2, Maths Q4

Question 4 of 90 in this shift, Maths question 4 of 30, Section A.

A

is a square matrix of order 3 such that

\det(A)=3

and

\det(\operatorname{adj}(-4\operatorname{adj}(-3\operatorname{adj}(3\operatorname{adj}((2A)^{-1}))))) = 2^m 3^n

, then

m+2n

is equal to :

(1)2
(2)4Official answer
(3)3
(4)6

Official answer

Option 2

NTA final key.

Chapter: Determinants
Topic: Matrix Inverse
Idea tested: Inverse Relation to Double Adjoint

Same idea in other shifts

Asked 8× in all

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.