Prove that :a(cosC-cosB)=2(b-c)cos^2 A

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If A + B + C = 2S, then prove that cos(S - A) + cos(S - B) + cos(S - C) = 4 cosA/2 cosB/2 cosC/2

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prove that sin(B+C/2) =cos(A/2)

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CONDITIONAL TRIGONOMETRIC IDENTITIES: If A+B+C=180, Prove that:- CosA/2+CosB/2+CosC/2=4Cos(pi-A/4)..

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If A + B + C = 180 Prove that cos2A + cos2B + cos2C = -1 - 4cosA cosB cosC

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If in a triangle `A B C ,cosA+2cosB+cosC=2` prove that the sides of the triangle are in `AP`

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If A+B+C=180 degree, prove that cos2A-cos2B-cos2C= 4cosA.cosB.cosC-1

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If `A+B+C=180 ,` prove that `cos^2A+cos^2B+cos^2C=1-2cosAcosBcosCdot`

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In any `DeltaABC, 2 [bc cos A + ca cos B+ ab cos C]=`

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6#IfCosA+CosB+CosC=0=SinA+SinB+SinC then Cos^2(A)+Cos^2(B)+Cos^2(C)=3/2=Sin^2(A)+Sin^2(B)+Sin^2(C)

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For any triangle ABC, prove that `(a-b)/c=(sin((A-B)/2))/(cosC/2)`...

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Cosine rule :b^2=a^2+c^2-2ac CosB derivation

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For any triangle ABC, prove that `a(bcosC-c cosB)=b^2-c^2`...

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For a triangle ABC, prove that cosA+cosB+cosC≤3/2.all angles are different

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`cosB-cosA=2((a-b)/c)cos^2C/2`

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If `A+B+C=pi` then prove that `cos(A/2)+cos(B/2)+cos(C/2)=4cos((pi-A)/4)cos((pi-B)/4)cos((pi-C)...

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`a( cos B + cos C) = 2(b +c) sin^(2)''(A)/(2)`.

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In any ∆ABC, prove cos2A/a^2 - cos2B/b^2 = 1/a^2 - 1/b^2

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Prove that a cosA + b cosB + c cosC = 2a sinB sinC

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If A+B+C=180° then prove that sinA+sinB+sinC=4cos(A/2)cos(B/2)cos(C/2)

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Prove that:- 4(bc cos²A/2 + ca cos²B/2 + ab cos²C/2 ) = (a + b + c)²

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In ` triangle ABC` prove that `(b^2-c^2)/(cos B+cos C) +(c^2-a^2)/(cos C+cos A) +(a^2-b^2)/(cos...

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Prove That(sin2A+sin2B+sin2C)/4cos(A/2)cos(B/2)cos(C/2)=8sin(A/2)sin(B/2)sin(C/2)|A+B+C=π|Opt Maths

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In any `Delta ABC` prove that : `a sin( (B-C)/2) = (b-c) cos (A/2)`

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prove that a sin (B - C)/2 = (b - c) cos A/2