nomor 8 dong kakk sama caranyaa:(

Bab Pola Bilangan

n = 5
a = 4
U5 = ar^(5 - 1)
324 = 4 × r^4
r^4 = 324/4
r^4 = 81
r = 3

Sn = a(r^n - 1)/(r - 1)
S5 = 4(3^5 - 1)/(3 - 1)
S5 = 4(243 - 1)/2
S5 = 2(242)
S5 = 484