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Equation for an Ellipse

Date: 10/27/95 at 16:44:28
From: Anonymous
Subject: Ellipse X,Y coordinates


I am trying to create objects along a ellipse.  I have the center
of the ellipse x,y coordinates, the lengths of both major and minor
radii, and the number of degrees up from the x axis.

I am looking for an equation where x1,y1 is the point on the ellipse 
to add my object.
				X1= ?
				Y1= ?

I found the right formula for a circle but can't find it for an ellipse.

If you could point me where to look or provide the equations I would 
be very grateful.

Bob Jensen 

Date: 11/19/95 at 16:35:18
From: Doctor Josh
Subject: Re: Ellipse X,Y coordinates

Dear Bob,
  The general equation for an ellipse is:

               (x^2)/a^2 + (y^2)/b^2 = 1

where a is the major axis, b is the minor axis (a > b > 0), the
major axis is along the x axis, and the center of the ellipse is at the
origin.  A good introduction to ellipses can be found in David M. 
Bressoud's book _Second Year Calculus_, published by Springer-Verlag.

-Doctor Josh,  The Geometry Forum

Associated Topics:
High School Equations, Graphs, Translations

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