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Topic: Evaluate Sum (Read 1305 times) |
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Benny
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Evaluate Sum
« on: Mar 17th, 2012, 9:59am » |
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n=1 to infinity SUM (48n)/(n^4+4)
= 12/(n^2 - 2n+2) - 12/(n^2 + 2n+2)
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If we want to understand our world — or how to change it — we must first understand the rational choices that shape it.
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pex
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Re: Evaluate Sum
« Reply #1 on: Mar 17th, 2012, 1:18pm » |
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on Mar 17th, 2012, 9:59am, Benny wrote:n=1 to infinity SUM (48n)/(n^4+4)
= 12/(n^2 - 2n+2) - 12/(n^2 + 2n+2) |
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It's ... eighteen ...
Hint: Complete the squares in the denominators of your last expression, and telescope.
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Benny
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Re: Evaluate Sum
« Reply #2 on: Mar 20th, 2012, 11:17am » |
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Thanks. I don't know how I missed that.
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If we want to understand our world — or how to change it — we must first understand the rational choices that shape it.
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