PM = PS wanted, semicircle with center M
Source: 2022 Austrian Mathematical Olympiad Junior Regional Competition , Problem 3
October 4, 2022
geometryequal segmentssemicircle
Problem Statement
A semicircle is erected over the segment with center . Let be one point different from and on the semicircle and the midpoint of the arc of the circle . The point of intersection of the straight line with the parallel to through is . Prove that holds.(Karl Czakler)