Three Dimensional Geometry · Class 12 · CBSE · Science Mathematics
The direction cosines of a line whose direction ratios are 2, -1 and 2 are:
Practice question from Three Dimensional Geometry (Class 12 · CBSE · Science Mathematics), with the correct answer and a step-by-step solution.
easy · MCQ · Q-95E828
The direction cosines of a line whose direction ratios are 2, -1 and 2 are:
- A.(2/3, -1/3, 2/3)Correct answer
- B.(2, -1, 2)
- C.(1/2, -1/2, 1/2)
- D.(2/√5, -1/√5, 2/√5)
Solution
The magnitude of the direction-ratio vector is . Hence, the direction cosines are .
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