Locus of Perpendicular Tangent Intersections to an Ellipse — Monge Circle
2019-11-14 07:11
This GeoGebra applet demonstrates a classical property of ellipses: the locus of intersection points of pairs of perpendicular tangents to an ellipse forms a circle, known as the Monge Circle or Director Circle. For a standard ellipse x²/a² + y²/b² = 1, the director circle has equation x² + y² = a² + b², centered at the ellipse's center with radius √(a²+b²). Users can interactively drag points to
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