MathDB
Loci of circumcenters

Source: 2017 China TST 5 P4

April 14, 2017
geometrycircumcircle

Problem Statement

Given a circle with radius 1 and 2 points C, D given on it. Given a constant l with 0<l20<l\le 2. Moving chord of the circle AB=l and ABCD is a non-degenerated convex quadrilateral. AC and BD intersects at P. Find the loci of the circumcenters of triangles ABP and BCP.