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#1 2008-04-08 17:19:25
- clooneyisagenius
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- Registered: 2007-03-25
- Posts: 56
Radius of convergence
Trying to find the radius of convergence of:
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#2 2008-04-08 17:24:37
- mikau
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- Registered: 2005-08-22
- Posts: 1,504
Re: Radius of convergence
ratio test, man! did you learn that, yet?
A logarithm is just a misspelled algorithm.
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#3 2008-04-08 17:31:44
- clooneyisagenius
- Member
- Registered: 2007-03-25
- Posts: 56
Re: Radius of convergence
He. Right. So I try doing that... and it gets pretty complicated quickly.
I get:
So, yes i did know that. But when I try to simplify its... not easy?
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#4 2008-04-08 19:48:26
- mikau
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- Registered: 2005-08-22
- Posts: 1,504
Re: Radius of convergence
its wonderfully easy! You're just not organizing it right. Invert the denominator and multiply it to get this:
using the product law for limits, you can separate these into three individual limits:
these you should be able to do yourself, but ask if you need help with any of them.
Last edited by mikau (2008-04-08 20:00:41)
A logarithm is just a misspelled algorithm.
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