JEE Main 2021 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 31 August 2021, Shift 2, Maths Q64

Question 64 of 90 in this shift, Maths question 4 of 30, Section A.

\alpha+\beta+\gamma = 2\pi

, then the system of equations

x+(\cos\gamma)y+(\cos\beta)z = 0

(\cos\gamma)x+y+(\cos\alpha)z = 0

(\cos\beta)x+(\cos\alpha)y+z = 0

has :

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

Official answer

Option 1

NTA final key.

Chapter: Determinants
Topic: Cramer's Rule
Idea tested: Homogeneous System Solutions

Same idea in other shifts

Asked 4× 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.