Christopher J. Bradley and Geoff C. Smith, The locations
of the Brocard points,
Forum Geometricorum, 6 (2006) 71--77.
Abstract: We fix and scale to constant size the orthocentroidal
disk of a variable non-equilateral triangle ABC. We show that the set of
points of the plane which can be either type of Brocard point consists of
the interior of the orthocentroidal disk. We give the locus of points which
can arise as a Brocard point of specified type, and describe this region
and its boundary in polar terms. We show that ABC is determined by the locations
of the circumcenter, the centroid and the Brocard points. In some circumstances
the location of one Brocard point will suffice.
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