Let ABC be an acute, non-isosceles triangle which is inscribed in a circle (O). A point I belongs to the segment BC. Denote by H and K the projections of I on AB and AC, respectively. Suppose that the line HK intersects (O) at M,N (H is between M,K and K is between H,N). Prove the following assertions:
1. If A is the center of the circle (IMN), then BC is tangent to (IMN). 2. If I is the midpoint of BC, then BC is equal to 4 times the distance between the centers of two circles (ABK) and (ACH).
Solution
See the solution to Problem 1 in the test of level 4+. □
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