" Life is not a problem to be solved but a reality to be experienced! "
© Copyright 2013 - 2024 KUDO.TIPS - All rights reserved.
a = 1
r = 3
Un = 243
Un = ar^n-1
243 = 3^n-1 (1 diabaikan karena setiap dikali satu bil.itusendiri)
dengan cara substitusi didapat
n - 1 = 5
n = 6
Sn = a(r^n-1) / r-1
S6 = 1(3^6-1) / 3-1
= 728/2
= 364 (D)