Let C1 and C2 be two concentric circles with C1 inside C2. Let P1 and P2 be two points on C1 that are not diametrically opposite. Extend the segment P1P2 past P2 until it meets the circle C2 in Q2. The tangent to C2 at Q2 and the tangent to C1 at P1 meet in a point X. Draw from X the second tangent to C2 which meets C2 at the point Q1. Show that P1X bisects angle Q1P1Q2.
geometryconcentricangle bisector