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cos C + cos D =...

cos C + cos D =

A

`2 "sin"(C+D)/2 "cos" (C-D)/2`

B

`2 "cos" (C+D)/2 "sin" (C-D)/2`

C

`2 "cos" (C+D)/2 "cos" (C-D)/2`

D

`2 "sin" (C+D)/2 "sin"(D-C)/2`

Text Solution

Verified by Experts

The correct Answer is:
B
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