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Evaluate cos^2(pi/8)+cos^2((3pi)/8)+cos^...

Evaluate `cos^2(pi/8)+cos^2((3pi)/8)+cos^2((5pi)/8)+cos^2((7pi)/8)=2`

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`(sqrt2-1)/2sqrt2`
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A N EXCEL PUBLICATION-TRIGONOMETRIC FUNCTIONS-QUESTION BANK
  1. Prove that cos^2theta=(1+cos2theta)/2

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  2. Evaluate cos^2(pi/8)+cos^2((3pi)/8)

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  3. Evaluate cos^2(pi/8)+cos^2((3pi)/8)+cos^2((5pi)/8)+cos^2((7pi)/8)=2

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  4. Prove that sinA/(1+cosA)=tan(A/2)

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  5. Show that tan 15^@ = 2 - sqrt3

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  6. Given that 1-costheta=2sin^2(theta/2) and 1+costheta=2cos^2(theta/2) p...

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  7. Given that 1-costheta=2sin^2(theta/2) and 1+costheta=2cos^2(theta/2)de...

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  8. Writing 4A=2xx2A prove that sin4A=4sinAcos^3A-4cosAsin^3A

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  9. if sin4A=4sinAcos^3A-4cosAsin^3A Dividing numerator and denominator on...

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  10. cosecA=1/sinA and cotA=cosA/sinA prove cosecA-cotA=tan(A/2)

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  11. Given that 1-costheta=2sin^2(theta/2) and 1+costheta=2cos^2(theta/2)de...

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  12. Given that tantheta=a/b find sin2theta and cos2theta

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  13. Given that tantheta=a/b prove that bcos2theta+asin2theta=b

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  14. Solve 2cos^2t+3sint=0

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  15. Solve sin2theta+costheta=0

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  16. solve sqrt3 costheta+sintheta=sqrt2

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  17. Find the principle and general solution of the following. tan x = s...

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  18. Find the principal and general solutions of the following equations s...

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  19. Find the principal and general solutions of the following equations ...

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  20. Find the principle and general solution of the following. cosec x =...

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