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The value of Pi(r=1)^(7)cos.(pi r)/(15) ...

The value of `Pi_(r=1)^(7)cos.(pi r)/(15)` is

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ALLEN-TRIGONOMETRIC RATIOS AND IDENTITIES-All Questions
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  2. The value of cos((2pi)/7)cos((4pi)/7)cos((6pi)/7) is a.-1//2 b. \ 1//...

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  3. The value of Pi(r=1)^(7)cos.(pi r)/(15) is

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  4. Prove that: s inpi/(14)s in(3pi)/(14)s in(5pi)/(14)s in(7pi)/(14)s in(...

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  5. Which of the following is correct?

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  6. Find the degrees and radians the angle between the hour hand and the ...

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  7. One angle of a triangle is (4x)/3 grades and another is 3x degrees, wh...

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  8. If in a Delta ABC, cot A + cot B + cot C = sqrt(3) . Prove that trian...

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  9. Length of E F is equal to- a.1+sqrt(3)-sqrt(6) b. \ 1+sqrt(3)-sqrt(2) ...

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  10. (log)(A E)((A C)/(C D)) is equal to a.sqrt(2) b. \ 1 c.\ 0 d. -1

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  11. Length of minor a r c(A C)i s- a.10pi b. \ 5pi c.\ 40\ pi/3 d. 20\ pi...

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  12. The value of (3-tan^2A)/(1-3tan^2A)+(3-tan^2B)/(1-3tan^2A)+(3-tan^2...

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  13. If cos(y-z)+cos(z-x)+cos(x-y)=-3/2, prove that cos x + cos y + cos z =...

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  14. Prove that cos 2a=2sin^(2)beta+4cos (alpha+beta)sin alpha sin beta+cos...

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