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If A+B+C=180^(@) then prove that sin"...

If `A+B+C=180^(@)` then prove that
`sin"A/2+"sin"B/2+"sin"C/2`
`=1+4sin((pi-A)/4)sin((pi-B)/4)cos((pi-C)/4)`

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AAKASH SERIES-TRANSFORMATIONS AND INDENTITIES-ADDITIONAL EXERCISE
  1. cos (B+C-A)-cos(C+A-B)+cos(A+B-C)- cos (A+B+C)=

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  2. If cosA=3/4 then show that "sin"A/2"sin"(5A)/2=11/32.

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  3. Show that cot(A+15^(@))-tan(A-15^(@))=(4cos2A)/(1+2sin2A) deduce tha...

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  4. Prove that cos alpha+cos beta+cos gamma+cos (alpha+beta+gamma) =4c...

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  5. Prove that 1+cos2x+cos4x+cos6x =4cosx cos 2x cos 3x

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  6. Prove that ((cos theta-cos 3 theta)(sin 8 theta +sin 2 theta))/((sin ...

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  7. Prove that (sin alpha+sin2 alpha+sin3alpha+sin4alpha)/(cos alpha+cos ...

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  8. Prove that 2 "cos"(pi)/13"cos"(9pi)/13+"cos"(3pi)/13+"cos"(5pi)/13=0

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  9. Prove that sin55^(@)-sin19^(@)+sin53^(@)-sin17^(@)=cos1^(@)

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  10. If A+B+C=180^(@) then prove that cos^(2)A+cos^(2)B-cos^(2)C=1-2sin ...

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  11. If A+B+C=180^(@) then prove that cos^(2)A+cos^(2)B+cos^(2)C=1-2cosA...

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  12. If A+B+C=180^(@) then prove that sin"A/2+"sin"B/2+"sin"C/2 =1+4si...

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  13. If A+B+C=0 then show that 1+cosA+cosB+cosC=4"cos"A/2"cos"B/2"cos"C/2

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  14. Prove that cos^(2)theta sin^(3)theta=1/16(2 sin theta+sin 3theta-sin...

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  15. Given alpha+beta-gamma=pi and sin^(2)alpha+sin^(2)beta-sin^(2)gamma=...

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  16. If 2 cos theta+2 cos 3 theta=cos alpha and 2 sin theta+2 sin 3 theta=s...

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  17. Show that tan20^(@)+4sin20^(@)=(sqrt(3))

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  18. Show that "cos"(pi)/65"cos"(2pi)/65"cos"(4pi)/65"cos"(8pi)/65"cos"(1...

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