Recall a geometric sequence is defined by an initial term a

Recall, a geometric sequence is defined by an initial term a and a constant ratio r(r notequalto 1): a, ar; ar^2, ..., a_r^n-1 A geometric series is just the Mini of the terms of this sequence: s = a + ar + ar^2 + ... + ar^n-1 = sigma_k=1^n ar^k-1 Your conjecture on how to compute the sum of a finite geometric series of n terms (the last problem of the WS) Also feel free to post any other insights or questions.

Solution

To find the sum of a finite geometric series

Sn = a(1-r^n)/(1-r), (r not equal to 1)

where n is the number of terms ,a is the first term and r is the common ration