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Let alpha , beta be such that pi lt a...

Let ` alpha , beta ` be such that `pi lt alpha - beta lt 3 pi ` . If ` sin alpha + sin beta =-(21)/(65) and cos alpha + cos beta =-(27)/(65)` , then the value of ` cos""(alpha - beta )/(2) ` is

A

`-3/sqrt(130)`

B

`3/sqrt(130)`

C

`6/65`

D

`-6/65`

Text Solution

Verified by Experts

The correct Answer is:
A
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