Posted by anonymous on .
find Sn for geometric sequence with A1 = 8, n = 9, and r = 1
Sn = A1 = 8, n = 9 and r = 1
Sn = A1(1r^n) / 1r
= 8(1  1^1)/(1(1))
= 8(0)/2
= 0
is this right ?

Algebra II 
Mgraph,
No.
Sn=8(1(1)^9)/(1(1))=8*2/2=8