Question about surface of revolution of parabola

makerbiles6 shared this question 3 months ago
Answered

I'm trying to model the parabola y=(x^2)/4, rotated around the y-axis, cut off at the top by the plane y=2. However, the only way I found is to use the paraboloid formula-- and then for some reason it's sideways from the y axis into z. I'd rather 'rotate' a parabola around y, and the sides go into z, if that makes sense. Is there a way to do that?

Comments (2)

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Whithout a sketch or a file with the parabola tyour despcription about y and x and the use of af the top, or sideways the y axis into z etc is not very clear to me. Are you sure about y and z and what you want?

Here's an anexample op a rotation of a parabola with limitid height with the Surface command: Surface(2sqrt(h) cos(t), 2sqrt(h) sin(t), h, h, 0, 2, t, 0°, 360°).If you want the parabola elsewhere you can exchange the expressions for x, y and/or z.

chris

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type


f(x)=x^2/4

g(x)=if(f(x)<=2,f(x))

surface(g,2 pi, yAxis)

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