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Prove that 2 cos""(pi)/(13)cos""(9pi)/(1...

Prove that `2 cos""(pi)/(13)cos""(9pi)/(13)+cos""(3pi)/(13)+cos""(15pi)/(13)=0`

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Prove that 2 cos""(pi)/(13)cos""(9pi)/(13)+cos""(3pi)/(13)+cos""(5pi)/(13)=0

cos""(2pi)/(15)cos""(4pi)/(15)cos""(8pi)/(15)cos""(16pi)/(15)=(1)/(16)

Show that cos (pi)/(15) cos""(2pi)/(15) cos"" (3pi)/(15) cos"" (4pi)/(15) cos"" (5pi)/(15) cos"" (6pi)/(15) cos"" (7pi)/(15) = (1)/(128) .

Prove that cos(2pi)/(15)cos(4pi)/(15)cos(8pi)/(15)cos(14pi)/(15)=1/(16)

The value of cos""(pi)/(11)+cos""(3pi)/(11)+cos""(5pi)/(11)+cos""(7pi)/(11)+cos""(9pi)/(11), is

Show that "cos"(pi)/(15)"cos"(2pi)/(15)"cos"(3pi)/(15)"cos"(4pi)/(15)"cos"(5pi)/(15)"cos"(6pi)/(15)"cos"(7pi)/(15)=(1)/(128) .

Show that 16cos((2pi)/(15))cos((4pi)/(15))cos((8pi)/(15))cos((16pi)/(15))=1

Show that 16cos((2pi)/(15))cos((4pi)/(15))cos((8pi)/(15))cos((16pi)/(15)) =1

Prove that 32 (sqrt(3)) sin"" (pi)/(48) cos"" (pi)/(48) cos"" (pi)/(24) cos"" (pi)/(12) cos"" (pi)/(6) = 3

Prove that sin (10pi)/(3) cos (13pi)/(6) + cos (8pi)/(3) sin (5pi)/(6) = -1

NEW JOYTHI PUBLICATION-TRIGONOMETRIC FUNCTIONS-QUESTIONS FROM COMPETITIVE EXAMS
  1. Prove that 2 cos""(pi)/(13)cos""(9pi)/(13)+cos""(3pi)/(13)+cos""(15pi)...

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  2. If A +B +C = 90 ^@ then ( cot A+ cot B + cot C) /(cot A cot B...

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  3. IF tan 20^@ = p , then (tan 160^@ - tan 110^@ )/( 1+ tan 160^...

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  4. the solution of sin ^3 theta cos theta - sin theta cos^3 theta ...

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  5. In a triangle ABC , a =2,b=3 and sin A = (2)/(3) then cos C=

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  6. In Delta ABC if a to 2C and b to 3C , then cos B tends...

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  7. If sin ( pi cos theta ) = cos ( pi sin theta) , then which of th...

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  8. The value of sin 12^@ sin 48^@ sin 54^@ is equal to

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  9. The shadow of a pole is sqrt(3) times longer the angle of eleva...

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  10. IF the sides of a triangle are x^2 + x+1 , x^2 -1 and 2x +1 ...

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  11. The value of cos 1^@ . Cos 2^@ , cos 3^@ cos 179 ^@ is equa...

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  12. IF cot ( alpha + beta ) =0 then sin ( alpha + 2 beta ) is equal...

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  13. The value of 4 sin A cos ^3 A -4 cos sin^3 A is equal to

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  14. if the solution for theta of cos p theta + cos q theta =0 p g...

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  15. Find the value of k for which ( cos x + sin x)""^2 + k sin x cos...

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  16. The angles of a triangle ABC, are in Arithmetic progression and if b :...

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  17. The angles of a triangle are in the ratio 1:3:5 then the grea...

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  18. A circular wire of radius 7 cms is cut and bend again into and ...

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  19. IF tan A + cot A=4 , then tan^4 A + cot ^4 A is equal to

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  20. If tan ( theta/2)=t then ( 1-t^2 )/( 1+t^2) is equal to

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  21. The period of the function y= sin 2x is

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