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Question
The principal solutions of cot x = -`sqrt3` are .................
Options
`pi/6 ,(5pi)/6`
`(5pi)/6 , (7pi)/6`
`(5pi)/6,(11pi)/6`
`pi/6,(11pi)/6`
Solution
`(5pi)/6,(11pi)/6`
cot x = `sqrt3`
cot x = `-"cot"(pi/6) = cot(pi-pi/6) = "cot" (2pi - pi/6)`
= `"cot"((5pi)/6) = cot ((11pi)/6)`
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