JEE Main 2021 · MathsNumerical answerNumerical valueHardMulti-step

JEE Main 25 February 2021, Shift 1, Maths Q82

Question 82 of 90 in this shift, Maths question 22 of 30, Section B.

Let

\mathrm{A} = \begin{bmatrix} x & y & z \\ y & z & x \\ z & x & y \end{bmatrix}

, where

x

y

and

z

are real numbers such that

x + y + z > 0

and

xyz = 2

. If

\mathrm{A}^2 = \mathrm{I}_3

, then the value of

x^3 + y^3 + z^3

is_________.

Official answer

NTA final key.

Chapter: Determinants
Topic: Matrix Multiplication
Idea tested: Powers of Square Matrices

Same idea in other shifts

Asked 21× 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 108 of the 174 JEE Main shifts held from 2017 to 2026.