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AP EAMCET202124 Aug 2021Morning ShiftMathematicsVector AlgebraActual

The number of values of m R for which the vectors i +2 j +m k and i +m j +2 k are collinear is

Options

  1. A2
  2. B3
  3. C1
  4. Dinfinite

Correct answer

C. 1

Step-by-step solution

Vectors i +2 j +m k and i +m j +2 k are collinear. aligned a & =a₁ i +b₁ j +c₁ k b & =a₂ i +b₂ j +c₂ k are collinear aligned Then, a₁ a₂ = b₁ b₂ = c₁ c₂ Now, a = i +2 j +m k and b = i +m j +2 k are collinear 1 1 = 2 m = m 2 After solving, we get m=2 Number of values of m is 1 .

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