Advanced Search

Question: Old problem with an ellipse

Question:Old problem with an ellipse

JAMET 420 Maple 2018
geometry animation circle plotting ellipse
September 13 2020
1

A triangle ABC with fixed B and C vertex is considered in the plane, A being variable so that b+c remains constant and equal to a given length L.
We call P, T, T' the points of contact of the exinscrit circle in the angle B with the sides BC, AB and AC respectively.
Show that P is fixed and is one of the vertex of the ellipse described by point A. What are the locus of T and T'? How to animate the drawing when A move ? Thank you.
Please Wait...