Determine Sn for the geometric series? f(1)=2, r=-2, n=12

1 Answer
Jun 21, 2018

S12=819011

Explanation:

the sum to n terms of a geometric sequence is

xSn=a(rn1)r1

where a is the first term and r the common ratio

here a=2,r=2 and n=12

S12=2((2)121)121

×××=2(40961)11=819011