[ª] , [©] , [^] , [¨]Perimeter of triangle which inscribes in a circle / Decoding the meaning of additional line(GC World : Various Problems ,MaxEMin)
A, B, and C are on a circle O.
When will the perimeter of ĢABC be maximized/minimized?
What is the role of this line?

GC/Win


Forum of Geometric Constructor by Y.Iijima