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COMEDK202510 May 2025Morning ShiftMathematicsVector AlgebraActual

The magnitude of the projection of the vector - +2 - k on the z -axis is

Options

  1. A1
  2. B- 1 6
  3. C1 6
  4. D2

Correct answer

A. 1

Step-by-step solution

Let the given vector be A = - i + 2 j - k . The z-axis is represented by the unit vector k . The projection of a vector A on a vector B is given by A B | B | . Here, B = k , so | B | = 1 . The projection of A on the z-axis is A k = (- i + 2 j - k ) k = -1 . The magnitude of the projection is |-1| = 1 . Answer: 1

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