MathDB
touchpoints of these circles with base of pyramid are concyclic

Source: Polish MO Recond Round 1977 p4

September 9, 2024
geometry3D geometrypyramidConcyclic

Problem Statement

A pyramid with a quadrangular base is given such that each pair of circles inscribed in adjacent faces has a common point. Prove that the touchpoints of these circles with the base of the pyramid lie on one circle.