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If cosx+cosy+cosalpha=0 and sinx+siny+si...

If `cosx+cosy+cosalpha=0` and `sinx+siny+sinalpha=0` then `cot((x+y)/2)=`

A

`sin alpha `

B

`cos alpha `

C

`cot alpha `

D

`sin ((x+y)/(2))`

Text Solution

Verified by Experts

The correct Answer is:
B
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