So Here's a few problems where I have to find the nth partial sum:
Given the equation
The sum of a Geometric series for a sequence such that it follows the general pattern starting at n=1. a is a constant, and
|r| < 1
If we let n go towards infinity, then
However, before I can begin dealing with infinity, I can't get the general equation for the sum up to the nth term. What am I doing wrong?
The Sequence is:
if we let a = 10 and r = 1/5, then from Sn I got
That's what I got. However the way it is done is:
let a = 2 and let r= 1/5
Manual calculation by hand shows the second method to be the correct one. While I accept it, I can't see what's wrong with the first.