Let OX,OY and OZ be three rays in the space, and G a point "between these rays" (i. e. in the interior of the part of the space bordered by the angles YOZ,ZOX and XOY). Consider a plane passing through G and meeting the rays OX,OY and OZ in the points A,B,C, respectively. There are infinitely many such planes; construct the one which minimizes the volume of the tetrahedron OABC. geometry3D geometrytetrahedrongeometry proposed