JEE Main 2022 · MathsNumerical answerNumerical valueHardMulti-step

JEE Main 26 July 2022, Shift 2, Maths Q30

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

The number of matrices

A=\begin{pmatrix}a&b\\c&d\end{pmatrix}

, where

a,b,c,d\in\{-1,0,1,2,3,\ldots..,10\}

, such that

A=A^{-1}

, is _______.

Official answer

NTA final key.

Chapter: Matrices
Topic: Matrix Inverse
Idea tested: Inverse of Involutory Matrices

Same topic in other shifts

All Matrix Inverse 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.