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JEE Main201910 Jan 2019Evening ShiftMathematicsVector AlgebraActual

Let α → = λ - 2 a → + b → and β → = 4 λ - 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 collinear, is:

Options

  1. A- 4
  2. B- 3
  3. C4
  4. D3

Correct answer

A. - 4

Step-by-step solution

∵ α → ,   β → are collinear then, λ - 2 4 λ - 2 = 1 3 ⇒ λ = - 4 .

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