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If S=cos^2(pi/n) + cos^2((2pi)/n) +....+...

If `S=cos^2(pi/n) + cos^2((2pi)/n) +....+ cos^2((n-1)pi)/n`, then S equals

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PATHFINDER-TRIGONOMETRIC RATIOS AND IDENTITIES-QUESTION BANK
  1. Given A=sin^2theta +cos^4theta. Then for all real values of theta, whi...

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  2. The minimum value of cos(cosx) is

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  3. If S=cos^2(pi/n) + cos^2((2pi)/n) +....+ cos^2((n-1)pi)/n, then S equa...

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  4. If cos5theta = acostheta +bcos^2theta + c.cos^5theta =d, then

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  5. prove that In an acute angled triangle ABC, secA+ secB+secCge6 is

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  6. If Tn=sin^ntheta+ cos^ntheta, then (T6-T4)/T6=m holds for value of m s...

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  7. Value of the expression 2sinx-cos2x is

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  8. The range of function tan(pi/4sin^2x) must be

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  9. The inequation 4sin3x+5ge4cos2x+5sinx

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  10. If 7cosx-24sinx=dcos(x+alpha), oltalphaltpi/2, be true for all x in R,...

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  11. Prove that abs(sinthetasin(60^@-theta)sin(60^@+theta)) le1/4 for all v...

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  12. In a Delta ABC

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  13. In a triangle tanA+tanB+tanC=6 and tanAtanB=2, then the values of tanA...

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  14. 0ltthetaltpi/2, if x=sum(n=0)^inftycos^(2n)theta,y=sum(n=0)^inftysin^(...

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  15. If tanalpha and tanbeta are the roots of the equation x^2+px+q=0 (pne0...

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  16. Let f(theta, alpha)= 2sin^2theta+4cos(theta+alpha)sintheta.sinalpha+co...

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  17. Let f(theta, alpha)= 2sin^2theta+4cos(theta+alpha)sintheta.sinalpha+co...

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  18. Let f(theta) = sqrt(a^2cos^2theta+b^2sin^2theta) + sqrt(a^2sin^2theta+...

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  19. Let f(theta) = sqrt(a^2cos^2theta+b^2sin^2theta) + sqrt(a^2sin^2theta+...

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  20. If cos(pi/7), cos((3pi)/7), cos((5pi)/7) are the roots of the equation...

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