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If the direction cosines of a line are ...

If the direction cosines of a line are `((1)/(c ) , (1)/(c ), (1)/(c ))` then :

A

`0ltclt1`

B

`cgt2`

C

`cgt0`

D

`c=+-sqrt(3)`

Text Solution

Verified by Experts

The correct Answer is:
D
If `1/c,1/c,1/c` are the direction cosines of a line, then
`1/(c^(2))+1/(c^(2))+1/(c^(2))=1impliesc=+-sqrt(3)`
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OBJECTIVE RD SHARMA ENGLISH-THREE DIMENSIONAL COORDINATE SYSTEM -Section I - Solved Mcqs
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