JEE Main 2026 · MathsMultiple choiceSingle correctHardMulti-step

JEE Main 4 April 2026, Shift 1, Maths Q5

Question 5 of 75 in this shift, Maths question 5 of 25, Section A.

Let

S=\left\{A=\begin{bmatrix}a&b\\c&d\end{bmatrix}: a,b,c,d\in\{0,1,2,3,4\}\text{ and }A^2-4A+3I=0\right\}

be a set of

2\times2

matrices. Then the number of matrices in

S

, for which the sum of the diagonal elements is equal to

4

, is:

(1) $20$
(2) $17$
(3) $21$
(4) $19$ Official answer

Official answer

Option 4

NTA final key.

Chapter: Matrices
Topic: Matrix Multiplication
Idea tested: Matrix Polynomials

Same topic in other shifts

All Matrix Multiplication questions

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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.