How to get the expression of the projection of a 3D circle on xOyPlane.

Nicholasfox shared this question 2 months ago
Answered

How to get the expression of the projection of a 3D circle on xOyPlane?

I've tried locusequation command but faild.

please help.

Best Answer
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I'm sure there's a nicer way, but this works


Sequence((x(Point(c, i)), y(Point(c, i))), i, 0, 0.9, 0.2)
Conic(Element(l1, 1),Element(l1, 2),Element(l1, 3),Element(l1, 4),Element(l1, 5))

Comments (7)

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3

I'm sure there's a nicer way, but this works


Sequence((x(Point(c, i)), y(Point(c, i))), i, 0, 0.9, 0.2)
Conic(Element(l1, 1),Element(l1, 2),Element(l1, 3),Element(l1, 4),Element(l1, 5))

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1

Unbelievable! Thank you very much.

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3

I do not know if nicer way

m1 = {{1, 0, 0}, {0, 1, 0}, {0, 0, 0}}

ApplyMatrix(m1, c)

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1

Thanks.

Is there a easy way to transform Parametric equations into Conic equations.

from:

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

to:

/AQqnOIAMxUaAAAAAAElFTkSuQmCC

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1

only the michael method. create five points and use conic tool

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3

he hecho varios intentos pero siempre se produce un objeto en 3D y para tener una conica hay que reducirlo a 2D usando coordenadas x e y

Files: foro.ggb
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1

Have a lesson, thanks.

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