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Let α =(λ -2) a+ b and β =(4λ -2) a+3 b, be two given vectors where vectors a and b are non-collinear. The value of λ for which vectors α and β are…

JEE Main 2019 — Mathematics Vectors & 3D Geometry

2019mcqeasy

Let α⃗=(λ−2)a⃗+b⃗\vec{\alpha }=(\lambda -2) \vec{a}+\vec{b}α=(λ−2)a+b and β⃗=(4λ−2)a⃗+3b⃗,\vec{\beta }=(4\lambda -2) \vec{a}+3\vec{b},β​=(4λ−2)a+3b, be two given vectors where vectors a⃗\vec{a}a and b⃗\vec{b}b are non-collinear. The value of λ\lambdaλ for which vectors α⃗\vec{\alpha }α and β⃗\vec{\beta }β​ are collinear, is:

Official previous-year question

Held on 10 Jan 2019 · Verified 6 Jul 2026.

Options

  1. A

    −4-4−4

  2. B

    −3-3−3

  3. C

    444

  4. D

    333

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