MathDB

77

Part of 1985 IMO Longlists

Problems(1)

Equilateral triangles inscribed in a circle

Source:

9/14/2010
Two equilateral triangles are inscribed in a circle with radius rr. Let AA be the area of the set consisting of all points interior to both triangles. Prove that 2A≥r23.2A \geq r^2 \sqrt 3.
geometrygeometry unsolved