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A tower subtends angles alpha,2 alpha, 3...

A tower subtends angles `alpha,2 alpha, 3 alpha` respectively at points A,B and C all lying on a horizontal line through the foot of the tower, Then `(AB)/(BC)=`

A

`(sin 3alpha)/(sin 2alpha)`

B

`1+2cos 2alpha`

C

`2 cos 2alpha`

D

`(sin 2alpha)/(sin alpha)`

Text Solution

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The correct Answer is:
B
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