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If A+B+C=pi , prove that : sin^2, A/2 + ...

If `A+B+C=pi` , prove that : `sin^2, A/2 + sin^2, B/2 -sin^2, C/2 =1-2 cos, A/2 cos, B/2 sin, C/2

A

`1-2 cos ""(A)/(2) cos ""(B)/(2) sin""(C )/(2)`

B

`1-2 cos ""(B)/(2) cos ""(C)/(2) sin""(A )/(2)`

C

`1-2 cos ""(C)/(2) cos ""(A)/(2) sin""(B )/(2)`

D

none

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A
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ML KHANNA-TRIGONOMETRY RATIOS AND IDENTITIES-PROBLEM SET (6) ( MULTIPLE CHOICE QUESTIONS)
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  2. sin^(2) A + sin ^(2) B +sin^(2) C =

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  3. If A+B+C=pi , prove that : sin^2, A/2 + sin^2, B/2 -sin^2, C/2 =1-2 co...

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  7. If in a triangle ABC, tan A + tan B + tanC has the value 6, then the v...

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  8. In a triangle ABC if tanA: tan B : tan C = 3:4:5 then the value of sin...

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  9. If A+B+C=pi, prove that tan^2A/2+tan^2B/2+tan^2C/2geq1.

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  10. If A+B+C=pi and A, B, C are acute positive angles and cotA cotB cotC =...

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  13. If x+y+z=pi //2, then tan y tan z + tan z tan x + tan x tan y =

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  14. If x+y+z =pi //2, then cot x +cot y +cot z=

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  15. In a triangle ABC, sum cot A cot B=

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  16. If A,B,C be the angles of a triangle, then sum (cot A + cot B)/( tan A...

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  17. Consider a triangle ABC such that cotA+cotB+cotC=cot theta. Now answe...

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  18. In a triangle ABC, if cot A + cot B + cotC =cot theta , then ( si...

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