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Prove that sin2A + sin2B + sin2C = 4sinA...

Prove that sin2A + sin2B + sin2C = 4sinA · sinB · sin C

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CENGAGE PUBLICATION-TRIGONOMETRIC FUNCTIONS-All Questions
  1. In triangle A B C ,/A=60^0,/B=40^0,a n d/C=80^0dot If P is the center ...

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  2. If cos3x+sin(2x-(7pi)/6)=-2 , then show that x is of the form π / 3(6...

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  3. Prove that sin2A + sin2B + sin2C = 4sinA · sinB · sin C

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  4. If H is the othrocenter of an acute angled triangle ABC whose circumci...

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  5. The number of solutions of the equation 1+cosx+cos2x+sinx+sin2x+sin3x=...

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  6. Let us consider the equation cos^4x/a+sin^4x/b=1/(a+b),x in[0,pi/2],a,...

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  7. If tanA=(1-cosB)/(sinB) , then tan2A=tanBdot

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  8. The total number of solution of cosx=sqrt(1-sin2x) in [0,2pi] is equal...

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  9. The maximum value of x^4ehat-x^2 is e^2 (b) e^(-2) (c) 12 e^(-2) (d...

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  10. Four numbers n1,n2,n3a n dn4 are given as n1=sin15^0-cos15^0,n2=cos93^...

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  11. If sin^3xcos3x+cos^3xsin3x=3/8, then the value of 8sin4x is

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  12. The equation sin^4x+cos^4x+sin2x+alpha=0 is solvable for

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  13. In triangle A B C , if r1=2r2=3r3, then a : b is equal to 5/4 (b) 4/5...

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  14. If cos alpha =1/2(x+1/x),cos beta=1/2(y+1/y) then evaluate cos(alpha-b...

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  15. In triangle A B C ,(sinA+sinB+sinC)/(sinA+sinB-sinC) is equal to

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  16. The radii r1,r2,r3 of enscribed circles of triangle ABC are in HP . If...

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  17. Let alphaa n dbeta be any two positive values of x for which 2cosx ,|c...

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  18. If (y+3)/(2y+5)=sin^2x+2cosx+1, then the value of y lies in the interv...

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  19. If alpha+beta+gamma=2pi, then (a) tan(alpha/2)+tan(beta/2)+tan(gamma...

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  20. The total number of solution of |cotx|=cotx+1/(sinx),x in [0,3pi] , is...

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