Diketahui deret geometri 4 + 8 + 16 + 32 +....tentukan jumlah 10 suku pertama

Mapel : Matematika
Kelas : IX SMP
Bab : Barisan dan Deret

Pembahasan :
4 + 8 + 16 + 32 + ...

Sn = a(r^n - 1)/(r - 1)
S10 = 4(2^10 - 1)
S10 = 4(1023)
S10 = 4.092

Deret geometri
a = 4
r = 8/4 = 2

r > 1

Sn = a((r^n) - 1) / (r - 1)
S10 = 4( (2^10) - 1) / (2 - 1)
S10 = 4 ( 1024 - 1)
S10 = 4(1023)
S10 = 4.092