MathDB

1

Part of 1973 USAMO

Problems(1)

Two Points in Regular Tetrahedron

Source: 1973 USAMO Problem 1

3/7/2010
Two points P P and Q Q lie in the interior of a regular tetrahedron ABCD ABCD. Prove that angle PAQ<60āˆ˜ PAQ < 60^\circ.
geometry3D geometrytetrahedron