Menu Close

cos-2pi-17-cos-4pi-17-cos-8pi-17-cos-16pi-17-




Question Number 135603 by liberty last updated on 14/Mar/21
cos (((2π)/(17)))+cos (((4π)/(17)))+cos (((8π)/(17)))+cos (((16π)/(17)))=?
$$\mathrm{cos}\:\left(\frac{\mathrm{2}\pi}{\mathrm{17}}\right)+\mathrm{cos}\:\left(\frac{\mathrm{4}\pi}{\mathrm{17}}\right)+\mathrm{cos}\:\left(\frac{\mathrm{8}\pi}{\mathrm{17}}\right)+\mathrm{cos}\:\left(\frac{\mathrm{16}\pi}{\mathrm{17}}\right)=? \\ $$

Leave a Reply

Your email address will not be published. Required fields are marked *