JEE Main 2021 · MathsNumerical answerNumerical valueEasyCalculation

JEE Main 25 July 2021, Shift 1, Maths Q82

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

Let

\vec{p}=2\hat{i}+3\hat{j}+\hat{k}

and

\vec{q}=\hat{i}+2\hat{j}+\hat{k}

be two vectors. If a vector

\vec{r}=\left(\alpha\hat{i}+\beta\hat{j}+\gamma\hat{k}\right)

is perpendicular to each of the vectors

\left(\vec{p}+\vec{q}\right)

and

\left(\vec{p}-\vec{q}\right)

, and

\left|\vec{r}\right|=\sqrt3

, then

|\alpha|+|\beta|+|\gamma|

is equal to _________.

Official answer

NTA final key.

Chapter: Vector Algebra
Topic: Cross Product
Idea tested: Unit Normal Vector Calculation

Same topic in other shifts

All Cross Product 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 42 of the 174 JEE Main shifts held from 2017 to 2026.