MathDB
circle

Source: Netherlands 1993

June 28, 2009
geometry3D geometryspheregeometry unsolved

Problem Statement

Let C C be a circle with center M M in a plane V V, and P P be a point not on the circle C C. (a) (a) If P P is fixed, prove that AP^2\plus{}BP^2 is a constant for every diameter AB AB of the circle C C. (b) (b) Let AB AB be a fixed diameter of C C and P P a point on a fixed sphere S S not intersecting V V. Determine the points P P on S S that minimize AP^2\plus{}BP^2.