Getting 3D parametric equation to work with x,y values

sal22 shared this question 2 months ago
Needs Answer

I have 2 questions.

1) I have a 3D parametric equation below that I would like to animate with geogebra but the Z variable (inputbox) doesn't seem to accept the x and y values. How can I fix this? (I've attached the ggb file also)


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The plot is suppose to look something like this.

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If you want to see how it was generated the Octave code can be found here

https://stackoverflow.com/q...


What I'm trying to model:

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1ce788c35723d42f523e20369d7935e1


2) How can I change the equation to have the sides be pushed up more and to the right at a steeper angle like the Lily Impeller image? The Left image is what I get plotting the equation and the right Image is what I'm trying to get to.

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Best Answer

Comments (3)

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2

One thing: instead of using x and y for z, I gues you have to repeat the expressions for x and y. So I guess you're getting something as Surface(u*sin(u)cos(u), u*cos(u)cos(v), -u*sin(v)-sin(pi/3)*sqrt((u*sin(u)cos(u))²+(u*cos(u)cos(v))²), u, 0°, 360°, v, 0°, 360°)Probably I missed something because the result is quite different.

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1

Thanks!!

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