Let C1 and C2 be circles in the same plane, P1 and P2 arbitrary points on C1 and C2 respectively, and Q the midpoint of segment P1P2. Find the locus of points Q as P1 and P2 go through all possible positions.
Alternative version. Let C1,C2,C3 be three circles in the same plane. Find the locus of the centroid of triangle P1P2P3 as P1,P2, and P3 go through all possible positions on C1,C2, and C3 respectively. geometry proposedgeometry