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If A+B+C=180^(@), then prove that cos^(2...

If `A+B+C=180^(@),` then prove that `cos^(2)(A)/(2)+cos^(2)(B)/(2)+cos^(2)(C)/(2)=2(1+sin(A)/(2)sin(B)/(2)sin(C)/(2))`

A

`1+2 sin""(A)/(2)sin""(B)/(2)sin""(C )/(2)`

B

`2+2 sin""(A)/(2)sin""(B)/(2)sin""(C )/(2)`

C

`1+2 cos""(A)/(2)cos""(B)/(2)cos""(C )/(2)`

D

`2+2 cos""(A)/(2)cos""(B)/(2)cos""(C )/(2)`

Text Solution

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The correct Answer is:
B
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ML KHANNA-TRIGONOMETRY RATIOS AND IDENTITIES-PROBLEM SET (6) ( MULTIPLE CHOICE QUESTIONS)
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