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If l(1), m(1), n(1) and l(2), m(2), n(2)...

If `l_(1), m_(1), n_(1)` and `l_(2), m_(2), n_(2)` are the direction cosines of two vectors and `theta` is the angle between them, then the value of cos `theta` is

A

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

B

`l_(1)m_(1) + m_(1)n_(1) + n_(1)l_(1)`

C

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

D

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

Text Solution

Verified by Experts

The correct Answer is:
A
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