Question

Perhatikan deret berikut: 1 + 2 + 4 + 8 + .... + k = 511. Nilai K adalah

Answer 1

Verified answer

Deret geometri
a= 1
r= 2/1= 2
Sn= a(r^n - 1) / r-1
511= 1 (2^n - 1) / 2-1
2^n - 1 = 511
2^n= 512
2^n= 2^9
n=9
k= U9= a.r^8= 1.2^8= 256

Answer 2

Verified answer

Diketahui:
a = 1
r = 2
Sn = 511

ditanya: nilai k/suku terakhir

jawab:

Sn = a(r^n - 1)/(r - 1)
511 = 1(2^n - 1)/(2 - 1)
511 = 1(2^n - 1)/1
511 = 2^n - 1
2^n = 511 + 1
2^n = 512
n = 9

k = u9

u9 = ar^8
k = 1(2^8)
k = 256

↓

jawaban: nilai k adalah 256.