Michel Bataille, On the foci of circumparabolas,
Forum Geometricorum, 11 (2011) 57--63.
Abstract. We establish some results about the foci of the infinitely many parabolas passing through three given points A, B, C. A very simple construction directly leads to their barycentric coordinates which provide, besides their locus, a nice and unexpected link with the foci of the parabolas tangent to the sidelines of triangle ABC.
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