JEE Main 2023MathematicsVector AlgebraEasyMCQ

JEE Main 2023 — Vector Algebra Question with Solution

JEE Main 2023 (25 Jan Shift 2)

Question

If the four points, whose position vectors are 3i^-4j^+2k^,i^+2j^-k^,-2i^-j^+3k^   and 5i^-2αj^+4k^ are coplanar, then α is equal to

Choose an option

Show full solutionCorrect option: A
Correct answer
A7317

Step-by-step explanation

Let the four points be A: (3,-4,2), B: (1,2,-1), C: (-2,-1,3) and D: (5,-2α, 4)

A, B, C, D are coplanar points, then

⇒1-32+4-1-2-2-3-1+43-25-3-2α+44-2=0

⇒-26-3-5312-2α+42=0

⇒-3α+146=0

⇒α=7317

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About this question

This is a previous-year question from JEE Main 2023, covering the Vector Algebra chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.