MathDB
<XAY >=60

Source: 2021 Korea Winter Program Test1 Day1 #2

February 5, 2021
geometry

Problem Statement

Let ABCABC be a triangle with ∠A=60∘\angle A=60^{\circ}. Point D,ED, E in lines AB→,AC→\overrightarrow{AB}, \overrightarrow{AC} respectively satisfies DB=BC=CEDB=BC=CE. (A,B,DA,B,D lies on this order, and A,C,EA,C,E likewise) Circle with diameter BCBC and circle with diameter DEDE meets at two points X,YX, Y. Prove that ∠XAY≥60∘\angle XAY\ge 60^{\circ}
Back to ProblemsView on AoPS