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Find the value of cos""(pi)/(11)+cos""(3...

Find the value of `cos""(pi)/(11)+cos""(3pi)/(11)+cos""(5pi)/(11)+cos""(7pi)/(11)+cos""(9pi)/(11)`.

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AAKASH INSTITUTE ENGLISH-TRIGNOMETRIC FUNCTIONS -Section I (subjective Type questions)
  1. Let f and g be function defined by f(theta)=cos^(2)theta and g(theta)=...

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  2. Let tanalpha = a/b, alpha being an acute angle. Denote by f(a,b) the v...

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  3. Find the value of cos""(pi)/(11)+cos""(3pi)/(11)+cos""(5pi)/(11)+cos""...

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  4. cot16^0cot44^0+cot44^0cot76^0-cot76^0cot16^0= 1 (b) 2 (c) 3 (d) ...

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  5. If cos(theta - theta(1)) =1/(2sqrt(3)) and sin(theta-theta(2))=1/(3sqr...

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  6. If cos(alpha-beta)+cos(beta-gamma)+cos(gamma-alpha)=-3/2 , prove that ...

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  7. If alpha and beta satisfy sinalpha cos beta=-1/2, then the greatest va...

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  8. If cos (pi/12) = (sqrt(2) + sqrt(6))/(4), then all x in (0,pi/2) such ...

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  9. In a DeltaABC if 3sinA+4 cosB=6, 4 sinB+3cosA=1 then possible value (s...

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  10. If (4 cos^(2)9^(@)-3)(4 cos^(2)27^(@)-3) =tanK^(@) , then K is equal ...

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  11. In triangle ABC, prove that the maximum value of tanA/2tanB/2tanC/2i s...

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  12. In a Delta ABC, angle B lt angle C and the values of B and C satisfy t...

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  13. If A ={ theta : 2cos^2 theta + sintheta <=2} , and B = {theta: pi/2<=t...

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  14. Solve 4cot2theta=cot^2theta-tan^2theta

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  15. If 3tan(theta-15^0)=tan(theta+15^0)0<theta<90^0 , find theta .

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  16. If cos 2theta=(sqrt(2)+1)(cos theta-(1)/(sqrt(2))), then the general v...

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  17. Solve the equation sin^(2)ntheta - sin^(2)(n-1)theta = sin^(2)theta

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  18. Solve the equation tan x + (cosx)/(sqrt(1+sin2x))=2.

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  19. Let x and y, (0 lt x, y lt pi/2) satisfy 3sin^(2)x + 2sin^(2)y=1 and 3...

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  20. If angles A and B satisfy sqrt(2)cosA = cosB + cos^(3)B and sqrt(2)sin...

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