JEE Main 2024 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 6 April 2024, Shift 2, Maths Q18

Question 18 of 90 in this shift, Maths question 18 of 30, Section A.

Let

\vec{a}=2\hat{i}+\hat{j}-\hat{k}

\vec{b}=\left(\left(\vec{a}\times(\hat{i}+\hat{j})\right)\times\hat{i}\right)\times\hat{i}

. Then the square of the projection of

\vec{a}

\vec{b}

is :

(1) $\frac{1}{3}$
(2)2Official answer
(3) $\frac{2}{3}$
(4) $\frac{1}{5}$

Official answer

Option 2

NTA final key.

Chapter: Vector Algebra
Topic: Triple Products
Idea tested: VTP with Repeated Vectors

Same topic in other shifts

All Triple Products 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.