שלושה מעגלים שנחתכים בנקודה אחת
- Author:
- lironchuk
- Topic:
- Circle
On sides (or their extensions) BC, CA and AB of triangle ABC points A1, B1
and C1 distinct from the vertices of the triangle are taken (one point on one side). Prove
that the circumscribed circles of triangles AB1C1, A1BC1 and A1B1C intersect at one point.