1. diketahui barisan 4, 12, 36, … . Tentukan jumlah 5 suku pertama!​

Prof Brainly Master

S5 = 4 (3⁵ – 1)/ 2

S5 = 484

Penjelasan dengan langkah-langkah:

4, 12, 36, …

a = 4

r = 12/4 = 3

Jumlah 5 suku pertama

Sn = a (r^n – 1)/(r – 1)

S5 = 4 (3^5 – 1)/(3 – 1)

S5 = 4 (242)/2

S5 = 484