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MHT CET20225 Aug 2022Evening ShiftMathematicsVector AlgebraActual

The sum of the lengths of projections of p i + q j + rk on the co-ordinate axes, where p=4, q=-5, r=7 is

Options

  1. A6 units
  2. B16 units
  3. C20 units
  4. D28 units

Correct answer

B. 16 units

Step-by-step solution

The projection on the x -axis =| p |=4 The projection on the y -axis =| q |=5 The projection on the z -axis =| r |=7 Sum =4+5+7=16

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