G2 Let ABC be an acute triangle. Let ω be a circle whose center L lies on the side BC. Suppose that ω is tangent to AB at B′ and to AC at C′. Suppose also that the circumcenter O of the triangle ABC lies on the shorter arc B′C′ of ω. Prove that the circumcircle of ABC and ω meet at two points.
Need to draw a picture to help me see what's going on.... |dw:1350953750613:dw| A little sloppy, but that's what I imagine it looks like. Seems pretty tightly constrained, so should be able to proved by relating the various properties of the circles.
Will have to use a lot of imagination to pretend that vertex A also touches the circumcircle, and that BC is a little straighter than I've drawn it, but again it shows some of the relative positions.
I'm thinking that a key point is the distance between the two circles is equal to the radius of ω, and the diameter of ω is larger than the radius of the circumcircle. I'm going to have to draw a better picture to visualize it, but I think that's a step in the right direction.
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