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$$ \int\limits_{x_1}^{x_2}\int\limits_{y_1}^{y_2}\int\limits_{z_1}^{z_2} \frac{1}{\sqrt{x^2+y^2+z^2}}\ dx\ dy\ dz $$ where $x_i, y_i, z_i \in \mathbb{R}$

I've tried to do it with command

Integrate[1/Sqrt[x^2+y^2+z^2],{x,x1,x2},{y,y1,y2},{z,z1,z2}]

but after few hours of evaluation I've got $Aborted message. I've tried to do it variable by variable but successfully done it only for z. Is it possible to calculate this in Mathematica and how?

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    $\begingroup$ Just work in spherical coordinates... $\endgroup$ – José Antonio Díaz Navas Nov 27 '17 at 7:10
  • $\begingroup$ @JoséAntonioDíazNavas it's easy for spherical coordinates even without Mathematica. In fact, all terms here can be integrated, first is $\ln \left| \frac{z_2+\sqrt{x^2+y^2+z_2^2}}{z_1+\sqrt{x^2+y^2+z_1^2}} \right|$, and so on. But expressions are too long to write them on paper $\endgroup$ – danielleontiev Nov 27 '17 at 7:15
  • $\begingroup$ I could help later when I have some time... $\endgroup$ – José Antonio Díaz Navas Nov 27 '17 at 7:19
  • $\begingroup$ @JoséAntonioDíazNavas, it would be great, thank you $\endgroup$ – danielleontiev Nov 27 '17 at 7:20
  • $\begingroup$ the problem changes character depending on if the origin is in the region. Have you tried Assumptions->{x2>x1>0,y2>y1>0,z2>z1>0 } ? (sorry cant test) It should at least fail faster.. $\endgroup$ – george2079 Nov 27 '17 at 20:39
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Here is what I get

Used Rubi for the indefinite integration part, since it gives simpler anti-derivatives, (no complex numbers show up). Then took the limits (assumed proper integrals)

 solR = Int[Int[Int[1/Sqrt[x^2 + y^2 + z^2], x], y], z]

Gives

(-(1/2))*z^2*ArcTan[(x*y)/(z*Sqrt[x^2 + y^2 + z^2])] - 
   (1/2)*y^2*ArcTan[(x*z)/(y*Sqrt[x^2 + y^2 + z^2])] - 
  (1/2)*x^2*ArcTan[(y*z)/(x*Sqrt[x^2 + y^2 + z^2])] + 
  y*z*ArcTanh[x/Sqrt[x^2 + y^2 + z^2]] + 
  x*z*ArcTanh[y/Sqrt[x^2 + y^2 + z^2]] + 
  x*y*ArcTanh[z/Sqrt[x^2 + y^2 + z^2]]

Now just took the limits, one at a time

solR2 = Assuming[Element[{z,y},Reals]&&x2>x1,
           Simplify[Limit[solR,x->x2]-Limit[solR,x->x1]]]
solR3 = Assuming[Element[{z,x1,x2},Reals]&&y2>y1&&x2>x1,
           Simplify[Limit[solR2,y->y2]-Limit[solR2,y->y1]]]
solR4 = Assuming[Element[{x1,x2,y1,y2},Reals]&&y2>y1&&x2>x1&&z2>z1,
           Simplify[Limit[solR3,z->z2]-Limit[solR3,z->z1]]]

And the result is

(1/2)*(z1^2*ArcTan[(x1*y1)/(z1*Sqrt[x1^2 + y1^2 + z1^2])] + y1^2*ArcTan[(x1*z1)/(y1*Sqrt[x1^2 + y1^2 + z1^2])] + x1^2*ArcTan[(y1*z1)/(x1*Sqrt[x1^2 + y1^2 + z1^2])] - 
   z1^2*ArcTan[(x2*y1)/(z1*Sqrt[x2^2 + y1^2 + z1^2])] - y1^2*ArcTan[(x2*z1)/(y1*Sqrt[x2^2 + y1^2 + z1^2])] - x2^2*ArcTan[(y1*z1)/(x2*Sqrt[x2^2 + y1^2 + z1^2])] - 
   z1^2*ArcTan[(x1*y2)/(z1*Sqrt[x1^2 + y2^2 + z1^2])] - y2^2*ArcTan[(x1*z1)/(y2*Sqrt[x1^2 + y2^2 + z1^2])] - x1^2*ArcTan[(y2*z1)/(x1*Sqrt[x1^2 + y2^2 + z1^2])] + 
   z1^2*ArcTan[(x2*y2)/(z1*Sqrt[x2^2 + y2^2 + z1^2])] + y2^2*ArcTan[(x2*z1)/(y2*Sqrt[x2^2 + y2^2 + z1^2])] + x2^2*ArcTan[(y2*z1)/(x2*Sqrt[x2^2 + y2^2 + z1^2])] - 
   z2^2*ArcTan[(x1*y1)/(z2*Sqrt[x1^2 + y1^2 + z2^2])] - y1^2*ArcTan[(x1*z2)/(y1*Sqrt[x1^2 + y1^2 + z2^2])] - x1^2*ArcTan[(y1*z2)/(x1*Sqrt[x1^2 + y1^2 + z2^2])] + 
   z2^2*ArcTan[(x2*y1)/(z2*Sqrt[x2^2 + y1^2 + z2^2])] + y1^2*ArcTan[(x2*z2)/(y1*Sqrt[x2^2 + y1^2 + z2^2])] + x2^2*ArcTan[(y1*z2)/(x2*Sqrt[x2^2 + y1^2 + z2^2])] + 
   z2^2*ArcTan[(x1*y2)/(z2*Sqrt[x1^2 + y2^2 + z2^2])] + y2^2*ArcTan[(x1*z2)/(y2*Sqrt[x1^2 + y2^2 + z2^2])] + x1^2*ArcTan[(y2*z2)/(x1*Sqrt[x1^2 + y2^2 + z2^2])] - 
   z2^2*ArcTan[(x2*y2)/(z2*Sqrt[x2^2 + y2^2 + z2^2])] - y2^2*ArcTan[(x2*z2)/(y2*Sqrt[x2^2 + y2^2 + z2^2])] - x2^2*ArcTan[(y2*z2)/(x2*Sqrt[x2^2 + y2^2 + z2^2])] - 
   2*y1*z1*ArcTanh[x1/Sqrt[x1^2 + y1^2 + z1^2]] - 2*x1*z1*ArcTanh[y1/Sqrt[x1^2 + y1^2 + z1^2]] - 2*x1*y1*ArcTanh[z1/Sqrt[x1^2 + y1^2 + z1^2]] + 2*y1*z1*ArcTanh[x2/Sqrt[x2^2 + y1^2 + z1^2]] + 
   2*x2*z1*ArcTanh[y1/Sqrt[x2^2 + y1^2 + z1^2]] + 2*x2*y1*ArcTanh[z1/Sqrt[x2^2 + y1^2 + z1^2]] + 2*y2*z1*ArcTanh[x1/Sqrt[x1^2 + y2^2 + z1^2]] + 2*x1*z1*ArcTanh[y2/Sqrt[x1^2 + y2^2 + z1^2]] + 
   2*x1*y2*ArcTanh[z1/Sqrt[x1^2 + y2^2 + z1^2]] - 2*y2*z1*ArcTanh[x2/Sqrt[x2^2 + y2^2 + z1^2]] - 2*x2*z1*ArcTanh[y2/Sqrt[x2^2 + y2^2 + z1^2]] - 2*x2*y2*ArcTanh[z1/Sqrt[x2^2 + y2^2 + z1^2]] + 
   2*y1*z2*ArcTanh[x1/Sqrt[x1^2 + y1^2 + z2^2]] + 2*x1*z2*ArcTanh[y1/Sqrt[x1^2 + y1^2 + z2^2]] + 2*x1*y1*ArcTanh[z2/Sqrt[x1^2 + y1^2 + z2^2]] - 2*y1*z2*ArcTanh[x2/Sqrt[x2^2 + y1^2 + z2^2]] - 
   2*x2*z2*ArcTanh[y1/Sqrt[x2^2 + y1^2 + z2^2]] - 2*x2*y1*ArcTanh[z2/Sqrt[x2^2 + y1^2 + z2^2]] - 2*y2*z2*ArcTanh[x1/Sqrt[x1^2 + y2^2 + z2^2]] - 2*x1*z2*ArcTanh[y2/Sqrt[x1^2 + y2^2 + z2^2]] - 
   2*x1*y2*ArcTanh[z2/Sqrt[x1^2 + y2^2 + z2^2]] + 2*y2*z2*ArcTanh[x2/Sqrt[x2^2 + y2^2 + z2^2]] + 2*x2*z2*ArcTanh[y2/Sqrt[x2^2 + y2^2 + z2^2]] + 2*x2*y2*ArcTanh[z2/Sqrt[x2^2 + y2^2 + z2^2]])

screen shot

Mathematica graphics

Quick verification

   solR4/.{x1->2,x2->3,y1->1,y2->5,z1->3,z2->9}//N

Mathematica graphics

    NIntegrate[1/Sqrt[x^2+y^2+z^2],{x,2,3},{y,1,5},{z,3,9}]

Mathematica graphics

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  • $\begingroup$ Thank you! It works for me. But how ArcTanh can be cobverted to Log form? $\endgroup$ – danielleontiev Nov 27 '17 at 7:46
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    $\begingroup$ @danielleontiev - to convert to Log form use expr // TrigToExp $\endgroup$ – Bob Hanlon Nov 27 '17 at 13:23
  • $\begingroup$ This function converts both ArcTan and ArcTanh, but I want only convert ArcTanh $\endgroup$ – danielleontiev Nov 27 '17 at 13:25
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    $\begingroup$ @danielleontiev - you can use a replacement rule if you want to be selective, expr /. x_ArcTanh :> TrigToExp[x] $\endgroup$ – Jason B. Nov 28 '17 at 5:11
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    $\begingroup$ Wow, Rubi is really impressive... $\endgroup$ – Henrik Schumacher Nov 28 '17 at 6:49
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There is no easy solution. See arXiv:chem-ph/9508002.

However, in the simplest case of a unit cube at the origin MA is able to compute the integral

 Integrate[1/Sqrt[x^2 + y^2 + z^2], {x, -1/2, 1/2}, {y, -1/2, 1/2}, {z, -1/2, 1/2}]
  (*-(\[Pi]/2) - 2 ArcSinh[1/Sqrt[2]] + Log[97 + 56 Sqrt[3]]*)
  FullSimplify[%]
  (*-(\[Pi]/2) + Log[26 + 15 Sqrt[3]]*)

Which is the same result as in the paper.

I would like to add that for a unit cube MA can produce results in many partial cases, for instance

 Integrate[1/Sqrt[x^2 + y^2 + z^2], {x, 0, 1}, {y, 0, 1}, {z, 0, 1}]
 (*-(\[Pi]/4) - ArcSinh[1/Sqrt[2]] + Log[7 + 4 Sqrt[3]]*)

 Integrate[1/Sqrt[x^2 + y^2 + z^2], {x, 1, 2}, {y, 1, 2}, {z, 1, 2}]
 (*(5 \[Pi])/4 - 8 ArcCot[2] + 8 ArcCot[3] - 8 ArcCot[2 Sqrt[6]] + 
  4 ArcSinh[1/(2 Sqrt[2])] - 3 ArcSinh[1/Sqrt[2]] + ArcSinh[Sqrt[2]] - 
  4 ArcTan[1/3] + 3/2 ArcTan[4/3] - 3 ArcTan[Sqrt[2/3]] + 
  2 ArcTan[1/(2 Sqrt[6])] + Log[2] - 2 Log[625] - Log[40960000] + 
  12 Log[1 + Sqrt[3]] + 12 Log[1 + Sqrt[6]] + 2 Log[2 + Sqrt[6]]*)

 Integrate[1/Sqrt[x^2 + y^2 + z^2], {x, 1, 2}, {y, -1/2, 1/2}, {z, -1/2, 1/2}]
  (* -8 ArcCot[12 Sqrt[2]] + 2 ArcCot[2 Sqrt[6]] - ArcSinh[Sqrt[2]] + 
 ArcSinh[2 Sqrt[2]] + ArcTan[Sqrt[2/3]] - ArcTan[(2 Sqrt[2])/3] + 
 8 Log[1 + 3 Sqrt[2]] - 2 Log[289/5 (7 + 2 Sqrt[6])]*)
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Often, Mathematica is quicker with indefinite integrals than with definite ones. It's annoying but a result is also producible as follows

int1 = Integrate[1/Sqrt[x^2 + y^2 + z^2], x];
int2 = Integrate[(int1 /. x -> x2) - (int1 /. x -> xx1), y];
int3 = Integrate[(int2 /. y -> y2) - (int2 /. y -> y1), z];
(int3 /. z -> z2) - (int3 /. z -> z1)

However, I would not rely on this result without further testing. (We might jump from one branch of, e.g. the complex logarithm to another.)

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For the case when all the integration limits are positive:

Clear[x2, x1, y2, y1, z2, z1, x, y, z];
myInt = Assuming[x2 > x1 > 0 && y2 > y1 > 0 && z2 > z1 > 0,
 Integrate[
  1/Sqrt[x^2 + y^2 + z^2], {x, x1, x2}, {y, y1, y2}, {z, z1, z2}]
 ];
FullSimplify[myInt]

$\frac{1}{4} \left(-i \log \left(\frac{\text{y1}^2+i \text{x1} \text{y1}+\text{z1} \left(\text{z1}+\sqrt{\text{x1}^2+\text{y1}^2+\text{z1}^2}\right)}{i \text{x1}+\text{y1}}\right) \text{y1}^2+i \log \left(\frac{\text{y1}^2+i \text{x2} \text{y1}+\text{z1} \left(\text{z1}+\sqrt{\text{x2}^2+\text{y1}^2+\text{z1}^2}\right)}{i \text{x2}+\text{y1}}\right) \text{y1}^2+i \log \left(\frac{\text{x1} \text{y1}+i \left(\text{y1}^2+\text{z1} \left(\text{z1}+\sqrt{\text{x1}^2+\text{y1}^2+\text{z1}^2}\right)\right)}{\text{x1}+i \text{y1}}\right) \text{y1}^2-i \log \left(\frac{\text{x2} \text{y1}+i \left(\text{y1}^2+\text{z1} \left(\text{z1}+\sqrt{\text{x2}^2+\text{y1}^2+\text{z1}^2}\right)\right)}{\text{x2}+i \text{y1}}\right) \text{y1}^2+i \log \left(\frac{\text{y1}^2+i \text{x1} \text{y1}+\text{z2} \left(\text{z2}+\sqrt{\text{x1}^2+\text{y1}^2+\text{z2}^2}\right)}{i \text{x1}+\text{y1}}\right) \text{y1}^2-i \log \left(\frac{\text{y1}^2+i \text{x2} \text{y1}+\text{z2} \left(\text{z2}+\sqrt{\text{x2}^2+\text{y1}^2+\text{z2}^2}\right)}{i \text{x2}+\text{y1}}\right) \text{y1}^2-i \log \left(\frac{\text{x1} \text{y1}+i \left(\text{y1}^2+\text{z2} \left(\text{z2}+\sqrt{\text{x1}^2+\text{y1}^2+\text{z2}^2}\right)\right)}{\text{x1}+i \text{y1}}\right) \text{y1}^2+i \log \left(\frac{\text{x2} \text{y1}+i \left(\text{y1}^2+\text{z2} \left(\text{z2}+\sqrt{\text{x2}^2+\text{y1}^2+\text{z2}^2}\right)\right)}{\text{x2}+i \text{y1}}\right) \text{y1}^2-4 \text{z1} \log \left(\text{x1}+\sqrt{\text{x1}^2+\text{y1}^2+\text{z1}^2}\right) \text{y1}+4 \text{z1} \log \left(\text{x2}+\sqrt{\text{x2}^2+\text{y1}^2+\text{z1}^2}\right) \text{y1}+4 \text{z2} \log \left(\text{x1}+\sqrt{\text{x1}^2+\text{y1}^2+\text{z2}^2}\right) \text{y1}+4 \text{x1} \log \left(\frac{\text{z2}+\sqrt{\text{x1}^2+\text{y1}^2+\text{z2}^2}}{\text{z1}+\sqrt{\tex t{x1}^2+\text{y1}^2+\text{z1}^2}}\right) \text{y1}-4 \text{z2} \log \left(\text{x2}+\sqrt{\text{x2}^2+\text{y1}^2+\text{z2}^2}\right) \text{y1}-4 \text{x2} \log \left(\frac{\text{z2}+\sqrt{\text{x2}^2+\text{y1}^2+\text{z2}^2}}{\text{z1}+\sqrt{\tex t{x2}^2+\text{y1}^2+\text{z1}^2}}\right) \text{y1}+4 \text{z1}^2 \tan ^{-1}\left(\frac{\text{x1} \text{y1}}{\text{z1} \sqrt{\text{x1}^2+\text{y1}^2+\text{z1}^2}}\right)-4 \text{z1}^2 \tan ^{-1}\left(\frac{\text{x2} \text{y1}}{\text{z1} \sqrt{\text{x2}^2+\text{y1}^2+\text{z1}^2}}\right)-4 \text{z1}^2 \tan ^{-1}\left(\frac{\text{x1} \text{y2}}{\text{z1} \sqrt{\text{x1}^2+\text{y2}^2+\text{z1}^2}}\right)+4 \text{z1}^2 \tan ^{-1}\left(\frac{\text{x2} \text{y2}}{\text{z1} \sqrt{\text{x2}^2+\text{y2}^2+\text{z1}^2}}\right)+2 \left(\left(\tan ^{-1}\left(\frac{\text{y1} \text{z1}}{\text{x1} \sqrt{\text{x1}^2+\text{y1}^2+\text{z1}^2}}\right)-\tan ^{-1}\left(\frac{\text{y2} \text{z1}}{\text{x1} \sqrt{\text{x1}^2+\text{y2}^2+\text{z1}^2}}\right)-\tan ^{-1}\left(\frac{\text{y1} \text{z2}}{\text{x1} \sqrt{\text{x1}^2+\text{y1}^2+\text{z2}^2}}\right)+\tan ^{-1}\left(\frac{\text{y2} \text{z2}}{\text{x1} \sqrt{\text{x1}^2+\text{y2}^2+\text{z2}^2}}\right)\right) \text{x1}^2+2 \text{y1}^2 \left(\tan ^{-1}\left(\frac{\text{x1} \text{z1}}{\text{y1} \sqrt{\text{x1}^2+\text{y1}^2+\text{z1}^2}}\right)-\tan ^{-1}\left(\frac{\text{x2} \text{z1}}{\text{y1} \sqrt{\text{x2}^2+\text{y1}^2+\text{z1}^2}}\right)-\tan ^{-1}\left(\frac{\text{x1} \text{z2}}{\text{y1} \sqrt{\text{x1}^2+\text{y1}^2+\text{z2}^2}}\right)+\tan ^{-1}\left(\frac{\text{x2} \text{z2}}{\text{y1} \sqrt{\text{x2}^2+\text{y1}^2+\text{z2}^2}}\right)\right)-2 \left(\left(\tan ^{-1}\left(\frac{\text{x1} \text{z1}}{\text{y2} \sqrt{\text{x1}^2+\text{y2}^2+\text{z1}^2}}\right)-\tan ^{-1}\left(\frac{\text{x2} \text{z1}}{\text{y2} \sqrt{\text{x2}^2+\text{y2}^2+\text{z1}^2}}\right)-\tan ^{-1}\left(\frac{\text{x1} \text{z2}}{\text{y2} \sqrt{\text{x1}^2+\text{y2}^2+\text{z2}^2}}\right)+\tan ^{-1}\left(\frac{\text{x2} \text{z2}}{\text{y2} \sqrt{\text{x2}^2+\text{y2}^2+\text{z2}^2}}\right)\right) \text{y2}^2+\text{z2}^2 \left(\tan ^{-1}\left(\frac{\text{x1} \text{y1}}{\text{z2} \sqrt{\text{x1}^2+\text{y1}^2+\text{z2}^2}}\right)-\tan ^{-1}\left(\frac{\text{x2} \text{y1}}{\text{z2} \sqrt{\text{x2}^2+\text{y1}^2+\text{z2}^2}}\right)-\tan ^{-1}\left(\frac{\text{x1} \text{y2}}{\text{z2} \sqrt{\text{x1}^2+\text{y2}^2+\text{z2}^2}}\right)+\tan ^{-1}\left(\frac{\text{x2} \text{y2}}{\text{z2} \sqrt{\text{x2}^2+\text{y2}^2+\text{z2}^2}}\right)\right)\right)+\text{x2}^2 \left(-\tan ^{-1}\left(\frac{\text{y1} \text{z1}}{\text{x2} \sqrt{\text{x2}^2+\text{y1}^2+\text{z1}^2}}\right)+\tan ^{-1}\left(\frac{\text{y2} \text{z1}}{\text{x2} \sqrt{\text{x2}^2+\text{y2}^2+\text{z1}^2}}\right)+\tan ^{-1}\left(\frac{\text{y1} \text{z2}}{\text{x2} \sqrt{\text{x2}^2+\text{y1}^2+\text{z2}^2}}\right)-\tan ^{-1}\left(\frac{\text{y2} \text{z2}}{\text{x2} \sqrt{\text{x2}^2+\text{y2}^2+\text{z2}^2}}\right)\right)\right)-4 \text{x1} \text{z1} \log \left(\text{y1}+\sqrt{\text{x1}^2+\text{y1}^2+\text{z1}^2}\right)+4 \text{x2} \text{z1} \log \left(\text{y1}+\sqrt{\text{x2}^2+\text{y1}^2+\text{z1}^2}\right)+4 \text{y2} \text{z1} \log \left(\text{x1}+\sqrt{\text{x1}^2+\text{y2}^2+\text{z1}^2}\right)+4 \text{x1} \text{z1} \log \left(\text{y2}+\sqrt{\text{x1}^2+\text{y2}^2+\text{z1}^2}\right)-4 \text{y2} \text{z1} \log \left(\text{x2}+\sqrt{\text{x2}^2+\text{y2}^2+\text{z1}^2}\right)-4 \text{x2} \text{z1} \log \left(\text{y2}+\sqrt{\text{x2}^2+\text{y2}^2+\text{z1}^2}\right)-i \text{z1}^2 \log \left(\frac{(\text{x1}-i \text{z1}) \text{z1}-i \text{y1} \left(\text{y1}+\sqrt{\text{x1}^2+\text{y1}^2+\text{z1}^2}\right)}{\text{x1}-i \text{z1}}\right)+i \text{z1}^2 \log \left(\frac{(\text{x1}+i \text{z1}) \text{z1}+i \text{y1} \left(\text{y1}+\sqrt{\text{x1}^2+\text{y1}^2+\text{z1}^2}\right)}{\text{x1}+i \text{z1}}\right)+i \text{z1}^2 \log \left(\frac{(\text{x2}-i \text{z1}) \text{z1}-i \text{y1} \left(\text{y1}+\sqrt{\text{x2}^2+\text{y1}^2+\text{z1}^2}\right)}{\text{x2}-i \text{z1}}\right)-i \text{z1}^2 \log \left(\frac{(\text{x2}+i \text{z1}) \text{z1}+i \text{y1} \left(\text{y1}+\sqrt{\text{x2}^2+\text{y1}^2+\text{z1}^2}\right)}{\text{x2}+i \text{z1}}\right)+i \text{z1}^2 \log \left(\frac{(\text{x1}-i \text{z1}) \text{z1}-i \text{y2} \left(\text{y2}+\sqrt{\text{x1}^2+\text{y2}^2+\text{z1}^2}\right)}{\text{x1}-i \text{z1}}\right)-i \text{z1}^2 \log \left(\frac{(\text{x1}+i \text{z1}) \text{z1}+i \text{y2} \left(\text{y2}+\sqrt{\text{x1}^2+\text{y2}^2+\text{z1}^2}\right)}{\text{x1}+i \text{z1}}\right)+i \text{y2}^2 \log \left(\frac{\text{y2}^2+i \text{x1} \text{y2}+\text{z1} \left(\text{z1}+\sqrt{\text{x1}^2+\text{y2}^2+\text{z1}^2}\right)}{i \text{x1}+\text{y2}}\right)-i \text{z1}^2 \log \left(\frac{(\text{x2}-i \text{z1}) \text{z1}-i \text{y2} \left(\text{y2}+\sqrt{\text{x2}^2+\text{y2}^2+\text{z1}^2}\right)}{\text{x2}-i \text{z1}}\right)+i \text{z1}^2 \log \left(\frac{(\text{x2}+i \text{z1}) \text{z1}+i \text{y2} \left(\text{y2}+\sqrt{\text{x2}^2+\text{y2}^2+\text{z1}^2}\right)}{\text{x2}+i \text{z1}}\right)-i \text{y2}^2 \log \left(\frac{\text{y2}^2+i \text{x2} \text{y2}+\text{z1} \left(\text{z1}+\sqrt{\text{x2}^2+\text{y2}^2+\text{z1}^2}\right)}{i \text{x2}+\text{y2}}\right)-i \text{y2}^2 \log \left(\frac{\text{x1} \text{y2}+i \left(\text{y2}^2+\text{z1} \left(\text{z1}+\sqrt{\text{x1}^2+\text{y2}^2+\text{z1}^2}\right)\right)}{\text{x1}+i \text{y2}}\right)+i \text{y2}^2 \log \left(\frac{\text{x2} \text{y2}+i \left(\text{y2}^2+\text{z1} \left(\text{z1}+\sqrt{\text{x2}^2+\text{y2}^2+\text{z1}^2}\right)\right)}{\text{x2}+i \text{y2}}\right)+4 \text{x1} \text{z2} \log \left(\text{y1}+\sqrt{\text{x1}^2+\text{y1}^2+\text{z2}^2}\right)-4 \text{x2} \text{z2} \log \left(\text{y1}+\sqrt{\text{x2}^2+\text{y1}^2+\text{z2}^2}\right)-4 \text{y2} \text{z2} \log \left(\text{x1}+\sqrt{\text{x1}^2+\text{y2}^2+\text{z2}^2}\right)-4 \text{x1} \text{z2} \log \left(\text{y2}+\sqrt{\text{x1}^2+\text{y2}^2+\text{z2}^2}\right)-4 \text{x1} \text{y2} \log \left(\frac{\text{z2}+\sqrt{\text{x1}^2+\text{y2}^2+\text{z2}^2}}{\text{z1}+\sqrt{\tex t{x1}^2+\text{y2}^2+\text{z1}^2}}\right)+4 \text{y2} \text{z2} \log \left(\text{x2}+\sqrt{\text{x2}^2+\text{y2}^2+\text{z2}^2}\right)+4 \text{x2} \text{z2} \log \left(\text{y2}+\sqrt{\text{x2}^2+\text{y2}^2+\text{z2}^2}\right)+4 \text{x2} \text{y2} \log \left(\frac{\text{z2}+\sqrt{\text{x2}^2+\text{y2}^2+\text{z2}^2}}{\text{z1}+\sqrt{\tex t{x2}^2+\text{y2}^2+\text{z1}^2}}\right)+i \text{z2}^2 \log \left(\frac{(\text{x1}-i \text{z2}) \text{z2}-i \text{y1} \left(\text{y1}+\sqrt{\text{x1}^2+\text{y1}^2+\text{z2}^2}\right)}{\text{x1}-i \text{z2}}\right)-i \text{z2}^2 \log \left(\frac{(\text{x1}+i \text{z2}) \text{z2}+i \text{y1} \left(\text{y1}+\sqrt{\text{x1}^2+\text{y1}^2+\text{z2}^2}\right)}{\text{x1}+i \text{z2}}\right)-i \text{z2}^2 \log \left(\frac{(\text{x2}-i \text{z2}) \text{z2}-i \text{y1} \left(\text{y1}+\sqrt{\text{x2}^2+\text{y1}^2+\text{z2}^2}\right)}{\text{x2}-i \text{z2}}\right)+i \text{z2}^2 \log \left(\frac{(\text{x2}+i \text{z2}) \text{z2}+i \text{y1} \left(\text{y1}+\sqrt{\text{x2}^2+\text{y1}^2+\text{z2}^2}\right)}{\text{x2}+i \text{z2}}\right)-i \text{z2}^2 \log \left(\frac{(\text{x1}-i \text{z2}) \text{z2}-i \text{y2} \left(\text{y2}+\sqrt{\text{x1}^2+\text{y2}^2+\text{z2}^2}\right)}{\text{x1}-i \text{z2}}\right)+i \text{z2}^2 \log \left(\frac{(\text{x1}+i \text{z2}) \text{z2}+i \text{y2} \left(\text{y2}+\sqrt{\text{x1}^2+\text{y2}^2+\text{z2}^2}\right)}{\text{x1}+i \text{z2}}\right)-i \text{y2}^2 \log \left(\frac{\text{y2}^2+i \text{x1} \text{y2}+\text{z2} \left(\text{z2}+\sqrt{\text{x1}^2+\text{y2}^2+\text{z2}^2}\right)}{i \text{x1}+\text{y2}}\right)+i \text{z2}^2 \log \left(\frac{(\text{x2}-i \text{z2}) \text{z2}-i \text{y2} \left(\text{y2}+\sqrt{\text{x2}^2+\text{y2}^2+\text{z2}^2}\right)}{\text{x2}-i \text{z2}}\right)-i \text{z2}^2 \log \left(\frac{(\text{x2}+i \text{z2}) \text{z2}+i \text{y2} \left(\text{y2}+\sqrt{\text{x2}^2+\text{y2}^2+\text{z2}^2}\right)}{\text{x2}+i \text{z2}}\right)+i \text{y2}^2 \log \left(\frac{\text{y2}^2+i \text{x2} \text{y2}+\text{z2} \left(\text{z2}+\sqrt{\text{x2}^2+\text{y2}^2+\text{z2}^2}\right)}{i \text{x2}+\text{y2}}\right)+i \text{y2}^2 \log \left(\frac{\text{x1} \text{y2}+i \left(\text{y2}^2+\text{z2} \left(\text{z2}+\sqrt{\text{x1}^2+\text{y2}^2+\text{z2}^2}\right)\right)}{\text{x1}+i \text{y2}}\right)-i \text{y2}^2 \log \left(\frac{\text{x2} \text{y2}+i \left(\text{y2}^2+\text{z2} \left(\text{z2}+\sqrt{\text{x2}^2+\text{y2}^2+\text{z2}^2}\right)\right)}{\text{x2}+i \text{y2}}\right)\right)$

$\endgroup$

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