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#1 2020-01-13 08:15:02
- mrpace
- Member
- Registered: 2012-08-16
- Posts: 88
Find the limit of this series
What does this series converge to?
16/3 + 32/9 + 16/27 + 32/81 + ......
Any help is appreciated
Thanks
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#2 2020-01-13 20:08:54
- Bob
- Administrator
- Registered: 2010-06-20
- Posts: 10,626
Re: Find the limit of this series
hi
This is two geometric series put together:
16 x (1/3 + 1/27 + …) + 32 x (1/9 + 1/81 + ...)
The common ratio is r = 1/9 for both. The start numbers are a = 1/3 and 1/9.
The formula for the sum to infinity of a GP is a/(1-r)
https://www.mathsisfun.com/algebra/sequ … etric.html
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob 
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