Mathematica How to draw integral with mathematica

AI Thread Summary
To draw the volume of a triple integral in Mathematica, users can utilize ParametricPlot3D or RegionPlot3D, focusing on plotting the limits of integration rather than the integral itself. For rectangular coordinates, a specific RegionPlot3D example is provided to visualize the integral limits effectively. In spherical coordinates, while SphericalPlot3D can be used, it may not render additional shapes like cones without further adjustments. Users are advised to convert spherical coordinates back to Cartesian for more complex shapes, which may require additional tweaking of angles. Overall, the discussion emphasizes the importance of correctly setting up the plots to visualize the desired volumes.
EliasS
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Hello,
is there a way to draw the volume of a triple integral?, and in different ways?(rectangular, cylindrical and sphere coordinates)
for example if the integral is
attachment.php?attachmentid=20391&stc=1&d=1252079429.jpg

what I want is to draw directly with the above formula
attachment.php?attachmentid=20392&stc=1&d=1252079429.jpg


I have been struggling all day with this, because if for example I use something like Plot3D[Integrate[x... it will first solve the integral, which will become a constant and then draw that constant

Also there must be a way because in the calculus book I'm studying, in many exercises it ask you to draw the volume of the problem with a software tool

Thank you, I really need this
 

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What you want to plot here is not the integrand nor the integral, what you want to plot is the limits of integration. I would use ParametricPlot3D or RegionPlot3D, but you will have to transform from spherical coordinates to Cartesian coordinates either way.
 
Thank you DaleSpam, now I can draw integrals in rectangular coordinates, for example, the integral

RegionPlot3D[-2 < x < 2 && -\[Sqrt](4 - x^2) < y < \[Sqrt](4 - x^2) && x^2 + y^2 < z < 4, {x, -2, 2}, {y, -2, 2}, {z, 0, 5}, PlotPoints -> 50, Mesh -> True, AxesLabel -> Automatic]
will draw

attachment.php?attachmentid=20427&stc=1&d=1252238163.jpg


but for spherical coordinates, I found the sentence SphericalPlot3D, which for example with
SphericalPlot3D[{1}, {\[Phi], 0, Pi/4}, {\[Theta], 0, 2 Pi}]
will draw

attachment.php?attachmentid=20428&stc=1&d=1252238468.jpg


but I doesn't draw the cone underneath the sphere, my question is, is there a way to do that?

I thought something like saying to mathematica "draw me rho from 0 to 1 continuously ", and it would draw

attachment.php?attachmentid=20429&stc=1&d=1252238468.jpg


, but the cone being solid

thank you
 

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I'd use region plot and just use spherical coordinates. Its slower, and requires tweaking due to the angles but :

r = Sqrt[x^2 + y^2 + z^2];
\[Phi] = ArcTan[y/Abs[x]];
\[Theta] = ArcCos[Abs[z]/Sqrt[x^2 + y^2 + z^2]];
RegionPlot3D[
0 < r <= 3 && 0 < Abs[\[Theta]] < \[Pi]/4, {x, -5, 5}, {y, -5,
5}, {z, 0, 5}, PlotPoints -> 60, Mesh -> True,
AxesLabel -> Automatic, PlotRange -> {{-3, 3}, {-3, 3}, {-1, 5}}]

http://en.wikipedia.org/wiki/Spherical_coordinatesSame for cylindrical. You just have to do a coordinate conversion back to cartesian.
 

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