Intersection of the Focus-Tangent Line with the Line from Vertex to Point of Contact

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Draw a tangent to a parabola and a line from the focus to that tangent. Draw another line from the tangency point to the vertex, and keep the angle between the two lines constant. The locus of intersections of the two lines forms an ellipse that passes through the focus and the vertex.

Expressions

Name Input
Locus Eq Derive Input Maple Input MathML Input Mathematica Input Maxima Input Mupad Input TI-Nspire Input text Input Image