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MHT CET202124 Sep 2021Morning ShiftMathematicsVector AlgebraActual

The projection of a = i -2 j + k on b =2 i - j + k is

Options

  1. A5
  2. B5 6
  3. C5 6
  4. D6

Correct answer

C. 5 6

Step-by-step solution

Projection a on b = a b | b | = ( i -2 j + k ) (2 i - j + k ) (2)^2+(-1)^2+(1)^2 = 2+2+1 6 = 5 6

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