Show that:

sin(2*pi/7) + sin(4*pi/7) + sin(8*pi/7) = √7/2

Note: All the angles are in radians.

(In reply to My solution! by Chesca Ciprian)

Well done CC.

I have incorporated your submitted methodology in my solution, since I do not know of any better one.

 

Edited on March 6, 2008, 4:27 am

Posted by K Sengupta on 2008-03-06 04:10:56