JEE Main 2024 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 4 April 2024, Shift 2, Maths Q17

Question 17 of 90 in this shift, Maths question 17 of 30, Section A.

Let

\vec a=\hat i+\hat j+\hat k,\ \vec b=2\hat i+4\hat j-5\hat k

and

\vec c=x\hat i+2\hat j+3\hat k,\ x\in\mathbb{R}

. If

\vec d

is the unit vector in the direction of

\vec b+\vec c

such that

\vec a\cdot\vec d=1

, then

(\vec a\times\vec b)\cdot\vec c

is equal to

(1)3
(2)6
(3)9
(4)11Official answer

Official answer

Option 4

NTA final key.

Chapter: Vector Algebra
Topic: Dot Product
Idea tested: Angle Between Vectors

Same idea in other shifts

Asked 6× 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.