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Prove that,"cos" pi/11 "cos" (2pi)/11 "c...

Prove that,`"cos" pi/11 "cos" (2pi)/11 "cos" (3pi)/11 "cos" (4pi)/11 "cos" (5pi)/11 = 1/32`

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CHHAYA PUBLICATION-TRIGONOMETRIC RATIOS OF MULTIPLE ANGLES-Long Answer Type Questions
  1. Prove that,tan theta tan (pi/3 + theta)tan (pi/3 - theta) = tan 3 thet...

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  2. Prove that,tan theta + 2 tan 2theta + 4 tan 4 theta + 8 cot 8 theta = ...

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  3. Prove that,"cos" pi/11 "cos" (2pi)/11 "cos" (3pi)/11 "cos" (4pi)/11 "c...

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  4. Prove that,If" " theta = (2pi)/7, " show that," sec theta + sec2 theta...

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  5. Prove that,If " "15 theta = pi, "show that," cos theta cos2 theta cos3...

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  6. If" " n tan alpha = (n+1) tan beta " then show that", tan (alpha - bet...

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  7. If tan theta = cos2 alpha tan phi, prove that tan (phi - theta) = (ta...

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  8. If tan theta = sec 2 alpha, "show that", sin 2 theta = (1-tan^(4) alph...

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  9. Prove that,8 cos^(4) theta = 3 + 4 cos 2 theta + cos 4 theta

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  10. Prove that,8 sin^(4) theta = 3 - 4 cos 2 theta + cos 4 theta

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  11. Prove that,64cos^(3) theta sin^(4) theta = cos 7 theta - cos 5 theta -...

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  12. Prove that,sin^(2)A cos^(4) A = 1/16 + 1/32 cos2A - 1/16 cos 4 A - 1/3...

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  13. If tan theta = ( tan alpha - tan beta)/(1-tan alpha tan beta),"show th...

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  14. If " "alpha " and " beta " are positive acute angles and " cos 2 alpha...

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  15. "If " (tan x)/(tan y) = (1 + cos^(2) x)/(1 + sin^(2) x ) " show that "...

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  16. If sin theta + sin 2 theta = a " and " cos theta + cos 2 theta = b, "...

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  17. If theta = pi/(2^(n) + 1), "show that",2^(n) cos theta cos 2 theta cos...

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  18. Prove that, (2 cos theta - 1)(2 cos 2 theta-1)(2 cos2^(2) theta-1)...(...

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  19. If x-1/x = 2i sin theta, "show that", x^(4)-1/x^(4)=2i sin 4 theta.

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  20. Show that,(x tan alpha + y cot alpha)( x cot alpha + y tan alpha) = (x...

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