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In a A B C , if cosC=(sinA)/(2sinB) , p...

In a ` A B C` , if `cosC=(sinA)/(2sinB)` , prove that the triangle is isosceles.

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RD SHARMA ENGLISH-SINE AND COSINE FORMULAE AND THEIR APPLICATIONS-All Questions
  1. In a right angled triangle ABC, write the value of sin^2 A + sin^2 B+ ...

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  2. Prove that, (asin(B-C))/(b^(2)-c^(2)) = (bsin(C-A))/(c^(2)-a^(2)) = ...

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  3. In a A B C , if cosC=(sinA)/(2sinB) , prove that the triangle is isos...

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  4. Problem on sine rule Type:-2 (i)The angle of elevation of the top of t...

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  5. (sqrt(sinA)-sqrt(sinB))/(sqrt(sinA)+sqrt(sinB)) = (a+b-2sqrt(ab))/(a-b...

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  6. Let O be a point inside a triangle A B C such that /O A B=/O B C=/O C ...

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  7. The angle of elevation of the top of a tower from a point A due south ...

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

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

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

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

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

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

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

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

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

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

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

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

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