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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)`

Text Solution

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The correct Answer is:
`2+ (r )/( 2R)`
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a cos ^(2) "" ( A) /(2) + b cos ^(2) "" ( B)/(2) = c cos ^(2) "" ( C) /(2) =