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Old August 17th, 2009, 06:23 PM
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Default Sequence and Series

Determine wether the series converges or diverges

(2+3^n) / (4^n) the summation goes from n=1 to n= infinity

I understand that you must split the problem up so you get (2/4^n) + (3/4)^n

I know how to get the second part as it is a gemoretic series. But i am stuck on the first half of the problem.
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Old August 17th, 2009, 06:27 PM
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Well \sum_{n=1}^\infty \frac{2}{4^n}=2\sum_{n=1}^\infty \frac{1}{4^n} which is also a geometric series...
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Old August 17th, 2009, 06:34 PM
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Quote:
Originally Posted by Bruno J. View Post
Well \sum_{n=1}^\infty \frac{2}{4^n}=2\sum_{n=1}^\infty \frac{1}{4^n} which is also a geometric series...

so does that mean that in that portion of the problem (1/4^n)

a=1/4 r=1/4 and you would use the formula a/1-r in order to find the sum
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Old August 17th, 2009, 07:05 PM
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a= 2 r = 1/4
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