tentukan Jumlah 10 suku pertama dari deret geometri 2,4,8

r=2
S10= (a(r^10-1))/(r-1)
→ (2(2^10-1))/(2-1)
→ (2(1024-1))/1
→ 2(1023)
→ 2046

a = 2
r = u2/u1 = 4/2=2

s10 = a(r^n-1)/r-1
= 2(2^10-1)/2-1

= 2.(1024-1)=2.1023=2046