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If A is not an integral multiple of `(pi)`, prove that `cos A cos 2A cos 4A cos 8A =(sin 16A)/(16 sin A)` Hence deduce that `cos. (2pi)/(15). Cos. (4pi)/(15) .cos. (8pi)/(18). Cos. (16pi)/(15)=(1)/(16)`

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SRISIRI PUBLICATION-QUESTION PAPER -Section B
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  2. If alpha,beta are the solutions of the equation acostheta+bsintheta=c...

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  3. If A is not an integral multiple of (pi), prove that cos A cos 2A cos ...

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  4. Solve sin x + sqrt(3) cos x = sqrt(2).

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  5. Solve that sqrt(2)(sinx+cosx)=sqrt(3)

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  6. Solve 2 cos^(2) theta - sqrt(3) sin theta + 1 = 0.

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  7. Solve 2 cos^(2) theta + 11 sin theta = 7.

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  8. Solve sin theta + sin 5 theta = sin 3 theta , 0 lt theta lt pi.

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  9. Solve 1+sin^2 theta=3sin thetacostheta

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  10. Solve tan theta + 3 cot theta = 5 "sec" theta.

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  11. If acos2theta+bsin2theta=c" has "theta(1),theta(2) as its solutions ...

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  12. Given pnepmq . Show that the solutions of cosPtheta+cosqtheta=0 for...

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  13. Prove that Sin^-1""3/5+Sin^-1""8/17=Cos^-1""36/85

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  14. P.T. Cos^(-1)((4)/(5))+Sin^(-1)((3)/(sqrt34))=Tan^(-1)((27)/(11)).

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  15. Find the value of tan(Sin^(-1)3/5 + Cos^(-1) 5/(sqrt34)).

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  16. Show that cos(2Tan^(-1).(1)/(7))=sin(2Tan^(-1).(3)/(4))

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  17. Prove that tan^(-1)((1)/(2))+tan^(-1)((1)/(5))+tan^(-1)((1)/(8))=(pi)/...

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  18. Prove that sin^(-1)((4)/(5))+2 Tan^(-1)((1)/(3)) = (pi)/2.

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  19. If Cos^(-1)p+Cos^(-1)q+Cos^(-1)r = pi then, P.T. p^(2)+q^(2)+r^(2) = 2...

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  20. Prove that sin[Cot^(-1) (2x)/(1-x^2)+Cos^(-1)((1-x^(2))/(1+x^(2)))]=1.

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