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Let fn(theta)=(cos(theta/2)+cos2theta+co...

Let `f_n(theta)=(cos(theta/2)+cos2theta+cos((7theta)/2)+....+cos(3n-2)(theta/2))/(sin(theta/2)+sin2theta+sin((7theta)/2)+....+sin(3n-2)(theta/2))` then (a)`f_3((3pi)/(16))=sqrt(2)-1` (b) `f_5(pi/(28))=sqrt(2)+1` (c)`f_7(pi/(60))=(2+sqrt(3))` (d) none of these

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CENGAGE PUBLICATION-TRIGONOMETRIC FUNCTIONS-All Questions
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