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If alpha=(pi)/(8 n) then prove that sin^...

If `alpha=(pi)/(8 n)` then prove that `sin^(2) alpha+ sin^(2)3 alpha+ sin ^(2) 5 alpha+..` to 2n terms =n.

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CHHAYA PUBLICATION-MISCELLANEOUS EXAMPLES-TRIGONOMETRY
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  2. If k is a positive integer, show that 2[ cos x+ cos 3x+ cos 5x+ ..+ ...

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  3. If alpha=(pi)/(8 n) then prove that sin^(2) alpha+ sin^(2)3 alpha+ sin...

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  4. If sin A+ tan A= a and cos A+ cot A= b, then show that (1+a)^(-2)+(1...

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  5. If a^(2)(1- sin theta) +b^(2)(1+ sin theta)= 2 ab cos theta then show ...

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  7. If n is positive integer and "cos" (pi)/(2n)+"sin" (pi)/(2n) =(sqrt(n)...

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  8. Solve : sec theta+"cosec" theta=2 sqrt(2)

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  9. Solve : tan^(3) theta+ cot^(3) theta= 8 "cosec"^(3) 2 theta+12

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  10. Solve : ("sin" (x)/(2) "cos" (x)/(2))/(1-8 "sin"^(2)(x)/(2) "cos"^(2...

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  14. The sides of a triangles are in A.P.and the greatest angle exceeds the...

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  15. Let 0 lt x lt pi, 0 lt y lt pi and cos x+ cos y - cos (x+y)=(3)/(2). ...

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  16. Eliminate x and y from the following equations : a sin ^(2)+ b cos^(2)...

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  17. Find the root of equation 2x^2+3 x + 11=0.

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  19. If alpha=(2pi)/(7) then prove that sin alpha sin 2 sin 4 alpha =-(sqrt...

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  20. If A,B,C are the angles of a triangle, show that that greatest value o...

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