Hi, I'm trying to get this working for a program I'm making. I've been working on this for a while, but I can't seem to figure it out.(adsbygoogle = window.adsbygoogle || []).push({});

I have multiplerotatedellipses. Imagine you took a rubber band and stretched it around the ellipses. The rubber band would follow the curve of the outside of an ellipse until it reached a point on the ellipse whose tangent line was the same as the tangent line of another point on the next ellipse. What I need to figure out is where those points are.

For each ellipse, I know: center x, center y, semimajor axis, semiminor axis, and the amount by which it has been rotated. So any ellipse E has known variables x, y, a, b, and theta.

I don't have equations for the ellipses, all I have are those variables.

How do I go about solving this?

Thanks in advance!

-Zippy Dee

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# Points on two ellipses with identical tangent lines

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