JEE Main 2023 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 11 April 2023, Shift 1, Maths Q6

Question 6 of 90 in this shift, Maths question 6 of 30, Section A.

Let

A

be a

2 \times 2

matrix with real entries such that

A' = \alpha A + I

, where

\alpha \in \mathbb{R} - \{-1, 1\}

. If

\det(A^2 - A) = 4

, then the sum of all possible values of

\alpha

is equal to

(1) $\frac{5}{2}$ Official answer
(2) $\frac{3}{2}$
(3)2
(4)0

Official answer

Option 1

NTA final key.

Chapter: Matrices
Topic: Matrix Multiplication
Idea tested: Transpose Reversal Law

Same topic in other shifts

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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.