MathDB
Sharygin 2016 (9-11)

Source:

April 13, 2016
geometry

Problem Statement

Let ABCABC be a triangle with C=90\angle C=90^{\circ}, and K,LK, L be the midpoints of the minor arcs AC and BC of its circumcircle. Segment KLKL meets ACAC,at point NN. Find angle NICNIC where IIis the incenter of ABCABC.