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In DeltaABC" prove that "cos^(2).(A)/(2...

In `DeltaABC" prove that "cos^(2).(A)/(2)+cos^(2).(B)/(2)+cos^(2).(C)/(2)=2+(r)/(2R)`

A

`(1)/(r)-(1)/(2R)`

B

`1+(r)/(R)`

C

`2+(r)/(2R)`

D

`1-(r)/(2R)`

Text Solution

Verified by Experts

The correct Answer is:
C
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