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Manipal MET2010MathematicsVector Algebra

Let u = i + j , v = i - j and w = i +2 j +3 k , if n is a unit vector such that u n =0 and v n =0 , then | w n | is equal to

Options

  1. A3
  2. B0
  3. C1
  4. D2

Correct answer

A. 3

Step-by-step solution

We have, u n =0 and v n =0 n u and n v n = u v | u v | Now, u v =( i + j ) ( i - j )=-2 k n = k Hence, | w n |=|( i +2 j +3 k ) ( k )|=3

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