Three Collinear Points Generated by a Tetrahedron
Publication Date
1-1-2023
Document Type
Article
Publication Title
Journal for Geometry and Graphics
Volume
27
Issue
1
First Page
29
Last Page
37
Abstract
Let ABCD be a tetrahedron. For each point P inside of the tetrahedron ABCD, there is a unique set of points {E, F, G, H, I, J} such that (1) E, F, G, H, I, and J are points on the edges DA, AB, BC, CD, AC, and BD, respectively, and (2) the segments EG, FH, and IJ concur at P. If the three planes FGJ, GHI, EHJ, intersect, say at A∗, then we will prove that the three points A, P, A∗ are collinear. Let A′ be the intersection of the line AP and the plane BCD. If the points B∗, C∗, D∗ are defined similar to A∗, and if the points B′, C′, D′ are defined similar to A′, we will find the volume of the tetrahedra A∗B∗C∗D∗ and A′B′C′D′. We use barycentric coordinates to prove these results.
Keywords
barycentric coordinates, collinear points, tetrahedron
Department
Mathematics and Statistics
Recommended Citation
Hidefumi Katsuura. "Three Collinear Points Generated by a Tetrahedron" Journal for Geometry and Graphics (2023): 29-37.