MathDB
inradius of P A_j A_{j+k} independent of P, if inradii of P A_iA_{i+1} are equal

Source: 15th -b QEDMO problem 10 (19. - 22. 10. 2017) https://artofproblemsolving.com/community/c1512515_qedmo_2005

May 30, 2021
geometryinradiusequal segments

Problem Statement

Let \ell be a straight line and PP \notin \ell be a point in the plane. On \ell are, in this arrangement, points A1,A2,...A_1, A_2,... such that the radii of the incircles of all triangles PAiAi+1P A_iA_{i + 1} are equal. Let kNk \in N. Show that the radius of the incircle of the triangle PAjAj+kP A_j A_{j + k} does not depend on the choice of jNj \in N .