Question

2. hitunglah jika diketahui 1 + 2 + 4 + 8 + ... + = 127
HARUS PAKAI CARA YANG LENGKAP

Answer 1

Deret geometri

r = 2/1 = 2

Un = a((r^n - 1) / (r - 1))
127 = 1((2^n - 1) / (2 - 1))
127 = (2^n - 1) / 1
127 = 2^n - 1
127 + 1 = 2^n
128 = 2^n
2^7 = 2^n
n = 7