anonymous one year ago Find the sum of the infinite geometric series 5+ 5/3+ 5/9+ 5/27...

1. anonymous

15/2

2. jim_thompson5910

first term is a = 5

3. jim_thompson5910

divide any term by the previous term to find the common ratio r r = (5/3) divided by 5 r = (5/3) times (1/5) r = (5*1)/(3*5) r = 5/15 r = 1/3 since |r| < 1 is true, this means we can use the formula $\Large S = \frac{a}{1-r}$

4. anonymous