[ª] , [©] , [^] , [¨]Tracks of incenterEexcenter / Doubt (1)(GC World : Various Problems ,Something strange?)
I got the following result when I left a track.

For example, itis not so doubtable if the motion of point A is restricted to the upper side of arc BC.

Why do two circles connect in such a strange shape?
What become of the rest of the circles?
This causes doubt.

GC/Win


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