5. For n ≥ 1, show that (a) 1+z+z²+...+2" = (1 - 2+¹)/(1-2), 1 (b) 1+ cos 0 + cos 20++ cos n0 = 2 z 1, sin (n + 1)0 2 si
Posted: Tue Jul 12, 2022 12:40 pm
5. For n ≥ 1, show that (a) 1+z+z²+...+2" = (1 - 2+¹)/(1-2), 1 (b) 1+ cos 0 + cos 20++ cos n0 = 2 z 1, sin (n + 1)0 2 sin 0/2 +