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a(cosC-cosB)=2(b-c)cos^2A/2...

`a(cosC-cosB)=2(b-c)cos^2A/2`

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To prove the equation \( a(\cos C - \cos B) = \frac{2(b - c) \cos^2 A/2}{1} \), we will start from the right-hand side and manipulate it step by step until we reach the left-hand side. ### Step-by-Step Solution: 1. **Start with the Right-Hand Side (RHS)**: \[ \text{RHS} = \frac{2(b - c) \cos^2 A/2}{1} \] ...
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RD SHARMA ENGLISH-SINE AND COSINE FORMULAE AND THEIR APPLICATIONS-All Questions
  1. The angle of elevation of the top of a tower from a point A due south ...

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  2. (bsecB+csecC)/(tanB+t a n C)=(csecC+asecA)/(tanC+t a n A)=(asecA+bsecB...

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  3. a(cosC-cosB)=2(b-c)cos^2A/2

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  4. a^2(cos^2B-cos^2C)+b^2(cos^2C-cos^2A)+c^2(cos^2A-cos^2B)=0 .

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  5. cos(2A)/a^2-cos(2B)/b^2 = 1/a^2-1/b^2

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  6. In a Delta A B C ,\ if\ a=2,\ b=3\ a n d\ sin A=2/3 then find /B

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  7. In any triangle A B C , prove that: ("sin"(B-C))/("sin"(B+C))=(b^2-c^2...

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  8. In any triangle A B C , prove that: \ asin(B-C)+b sin(C-A)+csin(A-B)=0

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  9. In any triangle A B C , prove that: \ a^3sin(B-C)+b^3sin(C-A)+c^3sin(A...

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  10. In any triangle A B C prove that: sin((B-C)/2)=((b-c)/a)cosA/2

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  11. In any triangle A B C , prove that: (b-c)/(b+c)=(tan((B-C)/2))/(tan((B...

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  12. In any triangle A B C , prove that: acos((B-C)/2)=(b+c)sin(A/2)

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  13. A tree stands vertically on a hill side which makes an angle of 15^0 w...

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  14. A person, standing on the bank of a river, observes that the angle sub...

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  15. The angle of elevation of to be top point P of the vertical tower PQ o...

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  16. The elevation of a tower at a station A due North of it is alpha and ...

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  17. If in a Delta A B C ,\ /A=45^0,\ /B=60^0,\ a n d\ /C=75^0 , find the ...

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  18. If in any Delta A B C ,\ /C=105^0,/B=45^0, a=2, then find bdot

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  19. In Delta A B C ,\ if\ a=18 ,\ b=24\ a n d\ c=30\ a n d\ /C=90^0 find ...

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  20. In any triangle A B C , prove that following : (a-b)/(a+b)=(tan((A-B)/...

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