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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,467

That could account for some of the differences.

I can plot that integrand but I do not understand the plot that I can see.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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What do you see?

I've tried plotting stuff and I get an empty graph.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,467

Hold on I will upload some images.

Might be easier to give the commands.

```
RegionPlot[((x^2 + y^2)^(-1/2)) (((100 - x)^2 + (100 - y)^2)^(-1/2))*
BesselJ[1, (x^2 + y^2)^(1/2)]*BesselJ[1, (((100 - x)^2 + (100 - y)^2)^(1/2))] > 0, {x, -10, 10}, {y, -10, 10}]
```

```
RegionPlot[((x^2 + y^2)^(-1/2)) (((100 - x)^2 + (100 - y)^2)^(-1/2))*
BesselJ[1, (x^2 + y^2)^(1/2)]*BesselJ[1, (((100 - x)^2 + (100 - y)^2)^(1/2))] < 0, {x, -10, 10}, {y, -10, 10}]
```

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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Thanks for the code. Those plots seem weird, but form an intriguing pattern.

*Last edited by zetafunc (2016-11-05 09:47:02)*

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,467

I have no idea what that means except it seems to indicate that integrand is sometimes positive and sometimes not.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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No responses yet on MO. Might be worth asking the same question on MathSE.

**LearnMathsFree: Videos on various topics.New: Integration Problem | Adding FractionsPopular: Continued Fractions | Metric Spaces | Duality**

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,467

I do not know how the entire world feels about that but I generally avoid doing that.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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It is either that or set up a bounty. (Or just solve it myself, of course.)

*Last edited by zetafunc (2016-11-07 01:16:57)*

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,467

Hi;

Bounties do not really make anyone smarter than they were before. Still, that is a possibility. How much will you offer?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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I'd offer the minimum if I were offering a bounty. But it might also be worth contacting my supervisor -- I haven't heard from him yet though (I sent him my proof on Thursday, but he's currently away so will probably not be able to get back to me for a while).

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,467

What place will you post the bounty?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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Maybe MathSE, because there are more people on there and I have 318 rep to spare there. On MO I only have 116.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,467

There are pros and cons. The people on the MathSE that could answer already have gazillions of rep points. A bounty may not interest them. The ones that might answer attracted by the bounty are more unknown.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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