Hiroshi Maehara, Horst Martini: On the Titeica-Johnson theorem, 231-237

Abstract:

We use planar circular inversions to show that the Titeica-Johnson theorem, Euler's triangle theorem, and the porism of triangles for two circles are all equivalent.

Key Words: Three-circles theorem, Euler's triangle theorem, Poncelet's porism.

2020 Mathematics Subject Classification: Primary 51M04; Secondary 51N20.

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