Ellipse Locus: Center of a Circle Tangent to Two Fixed Circles
2013-06-11 03:20
This applet demonstrates the ellipse locus. A moving circle is internally tangent to two fixed circles, tracing its center's path. This visually proves the sum of distances to the two fixed centers is constant, forming an ellipse. Input boxes allow dynamic radius adjustments to explore ellipse properties and foci. An excellent tool for coordinate geometry and geometric construction.
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Conic Sections | GeoGebra Book
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