Da Vinci's Ellipsograph: Geometric Construction of an Ellipse via Locus
2021-01-02 23:30
This example demonstrates the working principle of Da Vinci's ellipsograph (also known as the Trammel of Archimedes). A rod slides along two perpendicular tracks, and the locus of a fixed point on the rod traces an ellipse. The construction uses Point, Segment, Polygon, and Locus commands to visually illustrate the parametric generation of an ellipse. This classic geometric drawing instrument eleg
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Conic Sections - Interactive GeoGebra Book
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