MathDB
A and P equidistant from incenter

Source: KöMaL A 726

June 12, 2018
geometryincenter

Problem Statement

In triangle ABCABC with incenter II, line AIAI intersects the circumcircle of ABCABC at SAS\ne A. Let the reflection of II with respect to BCBC be JJ, and suppose that line SJSJ intersects the circumcircle of ABCABC for the second time at point PSP\ne S. Show that AI=PI.AI=PI.
József Mészáros