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COMEDK2019MathematicsVector Algebra

The projection of =3 i - j +5 k on v =2 i +3 j + R is

Options

  1. A8 35
  2. B8 39
  3. C8 14
  4. D14

Correct answer

C. 8 14

Step-by-step solution

Projection of a on b= a b |b| aligned &= (3 i - j +5 k ) (2 i +3 j + k ) |2 i +3 j + k | &= 6-3+5 4+9+1 = 8 14 aligned

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