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A=[{:(l(1),m(1),n(1)),(l(2),m(2),n(2)),(...

`A=[{:(l_(1),m_(1),n_(1)),(l_(2),m_(2),n_(2)),(l_(3),m_(3),n_(3)):}]` and `B=[{:(p_(1),q_(1),r_(1)),(p_(2),q_(2),r_(2)),(p_(3),q_(3),r_(3)):}]`
Where `p_(i), q_(i),r_(i)` are the co-factors of the elements `l_(i), m_(i), n_(i)` for `i=1,2,3`. If `(l_(1),m_(1),n_(1)),(l_(2),m_(2),n_(2))` and `(l_(3),m_(3),n_(3))` are the direction cosines of three mutually perpendicular lines then `(p_(1),q_(1), r_(1)),(p_(2),q_(2),r_(2))` and `(p_(3),q_(),r_(3))` are

A

the direction cosines of three mutually perpendicular lines

B

the direction ratios of three mutually perpendicular lines which are not direction cosines

C

the direction cosines of three lines which need be perpendicular

D

the direction ratios but not the direction cosines of three lines which need not be perpendicular

Text Solution

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The correct Answer is:
(a)
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