4

Part of 1989 Swedish Mathematical Competition

Problems(1)

locus wanted, edge tangent to sphere, regular terahedron ABCD

Source: 1989 Swedish Mathematical Competition p4

ABCD

be a regular tetrahedron. Find the positions of point

P

BD

such that the edge

CD

is tangent to the sphere with diameter

AP

geometry3D geometrytetrahedronLocussphere