JEE Main 2020 · MathsMultiple choiceSingle correctMediumConceptual

JEE Main 2 September 2020, Shift 2, Maths Q55

Question 55 of 75 in this shift, Maths question 5 of 25.

Let

A=\{X=(x,\ y,\ z)^T : PX=0

and

x^2+y^2+z^2=1\}

, where

P=\begin{bmatrix} 1 & 2 & 1 \\ -2 & 3 & -4 \\ 1 & 9 & -1 \end{bmatrix}

, then the set A :

(1)is an empty set.
(2)is a singleton.
(3)contains exactly two elements.Official answer
(4)contains more than two elements.

Official answer

Option 3

NTA final key (Sep 2020).

Chapter: Determinants
Topic: Cramer's Rule
Idea tested: Geometric Meaning of Non-Trivial Homogeneous Solutions

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.