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If cosA+cosB+cosC=0=sinA+sinB+sinC then ...

If `cosA+cosB+cosC=0=sinA+sinB+sinC` then `cos^(2)((A-B)/2)=`

A

`1//2`

B

`1//4`

C

`3//4`

D

1

Text Solution

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The correct Answer is:
B
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AAKASH SERIES-MULTIPLE & SUBMULTIPLE ANGLES-EXERCISE-II
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