TOT 1999 Autumn OS1 triangle by incenter similar to original triangle
Source:
May 11, 2020
geometryincentersimilar trianglessimilarangles
Problem Statement
The incentre of a triangle is joined by three segments to the three vertices of the triangle, thereby dividing it into three smaller triangles. If one of these three triangles is similar to the original triangle, find its angles. (A Shapovalov)