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In triangleABC, prove that cos((A+B)/(2)...

In `triangleABC`, prove that
`cos((A+B)/(2))=sinC/2`

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If A, B, C are interior angles of triangle ABC, prove that :- cos((B+C)/2)=sin(A/2) .

In triangleABC , prove that cos(A+B)+cosC=0

If A, B, C are interior angles of triangle ABC, prove that :- sin((A+C)/2)=cos (B/2) .

In any triangle ABC, prove that : cos frac (B-C)(2)= 2 sin frac (A)(2) , when b+c=2a .

In any triangle A B C , prove that: (1+cos(A-B)cos C)/(1+cos(A-C)cos B)=(a^2+b^2)/(a^2+c^2)

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If A, B, C are interior angles of triangle ABC, prove that :- cos^2(A/2)+cos^2((B+C)/2)=1 .

In any triangle A B C , prove that: (a^2sin(B-C))/(sinB+sin C)+(b^2sin(C-A))/(sinC+sin A)+(c^2sin(A-B))/(sinA+sin B)=0

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JBD PUBLICATION-TRIGNOMETRIC FUNCTIONS-EXAMPLE
  1. Prove that: cot^2frac (pi)(6)+cosecfrac (5pi)(6)+3tan^2frac (pi)(6)=6

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  2. In triangleABC, prove that cos(A+B)+cosC=0

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  3. In triangleABC, prove that cos((A+B)/(2))=sinC/2

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  4. Prove the following: cos((3pi)/2+x)cos(2pi+x)[cot((3pi)/2-x)+cot(2pi+x...

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  5. If tan alpha= (m)/(m+1) and tan beta=(1)/(2m+1), the find the value o...

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  6. If tan(alpha+theta)=ntan(alpha-theta), show that:(n+1)sin 2theta=(n-1)...

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  7. Prove that:(1+sin2x-cos2x)/(1+sin2x+cos2x)=tanx

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  8. Show that sqrt(2+sqrt(2+sqrt(2+2cos 8)))=2cos theta

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  9. Find sinfrac(x)(2), cosfrac(x)(2) and tanfrac(x)(2) in the following:-...

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  10. Find sinfrac(x)(2), cosfrac(x)(2) and tanfrac(x)(2) in the following:-...

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  11. Prove the following: (cos4x + cos3x + cos2x)/(sin4x + sin 3x + sin 2x)...

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  12. Show that:(sin11x sinx+sin7x sin3x)/(cos11x sinx + cos7x sin3x)=tan8x

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  13. Prove the following: sin2 x + 2 sin 4x + sin 6x = 4 cos^2 x sin 4x

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  14. Find the general solution for each of the following equations: 2cos^2x...

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  15. Find the general solution for each of the following equations: 4 sin^2...

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  16. Find the general solution of the following equations: sec^2 2x = 1- ta...

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  17. Find the general solution of the following trignometric equations: tan...

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  18. Find the general solution of the following trignometric equations: tan...

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  19. Prove that: (cosx-cosy)^2 +(sinx-siny)^2=4 sin^2frac (x-y)(2)

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  20. If sinx=3/5, cosy=-12/13, where x and y both lie in second quadrant, f...

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