JEE Main 2021 · MathsMultiple choiceSingle correctHardMulti-step

JEE Main 24 February 2021, Shift 2, Maths Q67

Question 67 of 90 in this shift, Maths question 7 of 30, Section A.

Let A and B be

3\times3

real matrices such that A is symmetric matrix and B is skew-symmetric matrix. Then the system of linear equations

(\mathrm{A^2B^2}-\mathrm{B^2A^2})\mathrm{X}=\mathrm{O}

, where X is a

3\times1

column matrix of unknown variables and O is a

3\times1

null matrix, has :

(1)no solution
(2)a unique solution
(3)exactly two solutions
(4)infinitely many solutionsOfficial answer

Official answer

Option 4

NTA final key.

Chapter: Matrices
Topic: Cramer's Rule
Idea tested: Skew-Symmetric Coefficient Matrices

Same topic in other shifts

All Cramer's Rule 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 108 of the 174 JEE Main shifts held from 2017 to 2026.