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NDA2015MathematicsThree Dimensional GeometryActual

The projections of a directed line segment on the coordinate axes are 12, 4, 3 respectively. What are the direction cosines of the line segment?

Options

  1. A12 13 , 4 13 , 3 13
  2. B12 13 ,- 4 13 , 3 13
  3. C12 13 ,- 4 13 ,- 3 13
  4. D- 12 13 ,- 4 13 , 3 13

Correct answer

A. 12 13 , 4 13 , 3 13

Step-by-step solution

Direction cosine of line segment = ( 12 13 , 4 13 , 3 13 ) Option (A) is correct.

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