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If "cosec"x=(2)/(sqrt(3)), cot x=-(1)/(s...

If `"cosec"x=(2)/(sqrt(3)), cot x=-(1)/(sqrt(3)), x in [0, 2pi]`, then `cosx +cos2x+cos3x+……+cos100x=`

A

`(1)/(2)`

B

`-(1)/(2)`

C

`-(sqrt(3))/(2)`

D

`(sqrt(3))/(2)`

Text Solution

Verified by Experts

The correct Answer is:
B
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