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"cos"(2pi)/(7) +"cos"(4pi)/(7)+"cos"(6pi...

`"cos"(2pi)/(7) +"cos"(4pi)/(7)+"cos"(6pi)/(7)`

A

is equal to zero

B

lies between 0 and 3

C

is a negative number

D

lies between 3 and 6

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WB JEE PREVIOUS YEAR PAPER-QUESTION PAPER 2014-MULTIPLE CHOICE QUESTIONS
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  7. "cos"(2pi)/(7) +"cos"(4pi)/(7)+"cos"(6pi)/(7)

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  8. Suppose M= int(0)^(pi//2) (cos x)/(x+2) dx, N=int(0)^(pi//4) (sinx" "c...

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  9. For any two real numbers theta and varphi, we define thetaR varphi if ...

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  13. Let t(n) denote the nth term of the infinite series (1)/(1!) +(10)/(2!...

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  17. The angle of intersection between the curves y=[|sinx| +|cosx|] and x^...

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  18. Let f(x)={(int(0)^(x)|1-t|dt",",x gt1),(x-(1)/(2)"," , x le 1):} The...

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