Japanese theorem of a quadrilateral inscribed in a circle

alatorre (Alejandro Latorre Chirot) February 17, 2026, 1:58pm 1

By triangular an arbitrary cyclic quadrilateral through its diagonals, four overlappiing triangles are obtained (each diagonal create two triangles). The centers of the inscribed circles of these
triangles form a rectangle.

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Japanese theorem of a quadrilateral inscribed in a circle

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