shehry1
Oct29-08, 12:28 AM
Can anyone tell me what is the sum of a finite series of Sines.
\sum_{n=1}^N \sin^2 (n \phi) . I am going through a text and it gives it as (N+1)/2. I tried to derive it. The N comes out ok when you use the half angle identity but I can't figure out a general rule for the Cosines that appear
\sum_{n=1}^N \sin^2 (n \phi) . I am going through a text and it gives it as (N+1)/2. I tried to derive it. The N comes out ok when you use the half angle identity but I can't figure out a general rule for the Cosines that appear