Jawabanmu

2014-04-15T18:45:52+07:00
U1 = a = 8
U5 = ar^4 = 1 
keduanya dibagi maka, r^3 = 1/8 => r = 1/2 
S6 = a(1-r^n)/1-r = 8(1-1/2^5)/1-1/2 = 2.8(1-1/32) = 16(31/32) = 15,5
2014-04-15T18:46:34+07:00
R = 1/2 a = 16 S6 = {16 (1 - 1/64 }/ (1-1/2) S6 = (16 - 1/4)/ 1/2 S6 = 15,75 x 2 S6 = 31,5