Class 12MathematicsThree Dimensional GeometrySystem of co-ordinates, Direction cosines and direction ratios, Projection
EasyIf the direction cosines of a line are $\frac{1}{c}, \frac{1}{c}, \frac{1}{c}$,then:
- A$2 < c < 3$
- B$c=\pm 3$
- C$c=\pm \sqrt{3}$
- D$c=\pm \frac{1}{\sqrt{3}}$
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