#Integration help

1 messages · Page 1 of 1 (latest)

rich shell
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$\int^{\infty}_{0}\frac1{x^n+1}dx$

My current method is contour integration, with the contour being a sector with a radius R (R goes to infinity); sector has its corner at 0. The contour contains only one nth root of unity within it

versed hillBOT
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No Lifer#GTFOanemia

next elmBOT
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rich shell
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my work so far:

fathom python
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Hm. Well, I don't know complex analysis, but I have derived the following a while ago.

rich shell
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$\oint_{\alpha}\frac1{z^n+1}dz = 2i\pi Res(f,e^{\frac{i\pi}{n}})$

(Take alpha as the contour which I'm integrating along and f as the weird function I'm integrating)

$\oint_{\alpha}\frac1{z^n+1}dz = 2i\pi\lim_{z\to e^{\frac{i\pi}{n}}}\frac{z-e^{\frac{i\pi}{n}}}{z^n-1}$

(I got stuck evaluating the limit)

$\oint_{\alpha} = \int^{\infty}{0}\frac1{z^n+1}dz + \int{\Gamma}\frac1{z^n+1}dz + \int_{l}\frac1{z^n+1}dz$

(Take capital gamma to be the curvy part of the sector and l to be the tilted line part of the sector)

The integral along gamma then goes to zero as R goes to infinity (Benefits of abusing Jordan's Lemma)

$\oint_{\alpha} = \int^{\infty}{0}\frac1{z^n+1}dz + \int{l}\frac1{z^n+1}dz$

fathom python
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You can just type it.

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I'm sure people will understand.

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If you need symbols, I can provide you what you need.

rich shell
swift oliveBOT
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@rich shell has given 1 rep to @fathom python

fathom python
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Ah, ok.

versed hillBOT
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No Lifer#GTFOanemia

rich shell
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that looks horrendous-
I sincerely apologize to anyone reading this

fathom python
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Why? Looks nice to me.
Or did you mean the content? In that case, can't say anything about it.

rich shell
fathom python