Trigonometric Sum: cos(2pi/28)*csc(3pi/28) + cos(6pi/28)*csc(9pi/28) + cos(18pi/28)*

[lampat]

The value of \(\displaystyle \displaystyle \cos \left(\frac{2\pi}{28}\right)\cdot \csc \left(\frac{3\pi}{28}\right)+\cos \left(\frac{6\pi}{28}\right)\cdot \csc \left(\frac{9\pi}{28}\right)+\cos \left(\frac{18\pi}{28}\right)\cdot \csc \left(\frac{27\pi}{28}\right)\)

 

[Ishuda]

The value of \(\displaystyle \displaystyle \cos \left(\frac{2\pi}{28}\right)\cdot \csc \left(\frac{3\pi}{28}\right)+\cos \left(\frac{6\pi}{28}\right)\cdot \csc \left(\frac{9\pi}{28}\right)+\cos \left(\frac{18\pi}{28}\right)\cdot \csc \left(\frac{27\pi}{28}\right)\)

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