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Prove that b cosB + c cosC = a cos ( B...

Prove that
b cosB + c cosC = a cos ( B-C)

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In Delta ABC prove that (b+c)/a = (cosB + cosC)/(1-cosA)

In Delta ABC prove that a(cosB + cosC) = 2(b+c) sin^2(A/2)

Prove that a sinA - b sinB = c sin(A-B)

In Delta ABC prove that a^2(cos^2B - cos^2C) + b^2(cos^2C - cos^2A) + c^2(cos^2A - cos^2B) = 0

In Delta ABC prove that a^3cos(B-C) + b^3cos(C-A) + c^3 cos(A-B) = 3abc

Prove that if (a + b+ c)(b + c - a) = 3bc then A = 60^@

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MBD PUBLICATION-TRIGONOMETRIC FUNCTIONS-QUESTION BANK
  1. Fill int the blanks choosing correct answer from the bracket. If a =...

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  2. Prove that a sinA - b sinB = c sin(A-B)

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  3. Prove that b cosB + c cosC = a cos ( B-C)

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  4. Prove that if (a + b+ c)(b + c - a) = 3bc then A = 60^@

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  5. Prove that If (b+c)/5 = (c+a)/6 = (a+b)/7 then sinA : sinB : sinC ...

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  6. Prove that If A : B: C = 1: 2: 3 then sinA : sinB : sinC = 1:sqrt3...

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  7. Prove that b^2 + c^2 -a^2 = bc, then A = 60^@

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  8. Prove that If A: B: C = 1: 2: 7, then c:a =(sqrt5+1) : (sqrt5-1)

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  9. If cosA = 12/13 , cosB = 5/13, then find a:b.

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  10. If a = 7 , b= 3, c=5 then find A.

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  11. If a = 8,b=6 , C= 4 find tan B/2.

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  12. If a/(secA) = b/(secB) and a ne b then find C.

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  13. If a = 48, b= 35 ,angleC = 60^@ then find c.

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  14. In Delta ABC prove that a sin(B-C) + bsin(C-A) + c sin(A-B) = 0

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  15. In Delta ABC prove that a sin(B-C) + bsin(C-A) + c sin(A-B) = 0

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  16. In Delta ABC prove that sin(B-C)//sin(B+C) = (bcosC - c cosB)//(bcos...

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  17. In Delta ABC prove that sum a^2sin(B-C)//sin(B+C) = 0

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  18. In Delta ABC prove that a^2(cos^2B - cos^2C) + b^2(cos^2C - cos^2A) ...

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  19. In Delta ABC prove that (b^2-c^2)/(a^2) sin2A + (c^2-a^2)/(b^2) sin2...

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  20. In Delta ABC prove that a^2(b^2 + c^2 - a^2)/(sin2A) = b^2(c^2 + a^2...

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