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The direction cosines of a line equally ...

The direction cosines of a line equally inclined to three mutually perpendiclar lines having direction cosines as `l_(1),m_(1),n_(1),l_(2),m_(2),n_(2)` and `l_(3), m_(3),n_(3)` are

A

`l_(1)+l_(2)+l_(3),m_(1)+m_(2)+m_(3),n_(1)+n_(2)+n_(3)`

B

`(l_(1)+l_(2)+l_(3))/(sqrt(3)),(m_(1)+m_(2)+m_(3))/(sqrt(3)),(n_(1)+n_(2)+n_(3))/(sqrt(3))`

C

`(l_(1)+l_(2)+l_(3))/(3),(m_(1)+m_(2)+m_(3))/(3),(n_(1)+n_(2)+n_(3))/(3)`

D

none of these

Text Solution

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The correct Answer is:
B
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