Isogonal conjugates in a tetrahedron - Jawad Sadek, Magid Bani-Yaghoub and Noah H. Rhee The symmedian point of a tetrahedron is defined and the existence of the symmedian point of a tetrahedron is proved through a geometrical argument. It is also shown that the symmedian point and the least squares point of a tetrahedron are concurrent. We also show that the symmedian point of a tetrahedron coincides with the centroid of the corresponding pedal tetrahedron. Furthermore, the notion of isogonal conjugate to tetrahedra is introduced, with a simple formula in barycentric coordinates. In particular, the barycentric coordinates for the symmedian point of a tetrahedron are given. ✪ ✪ ✪ ✪ ✪ Hidden Content: **Hidden Content: Content of this hidden block can only be seen by members of (usergroups: V.I.P Downloader).** Theo LTTK Education
