Tetraeder Geometry

Introductory Geometry: Algebraic Geometry

The Variable Geometry Approach to International

Negotiations among nations on policies to promote international economic integration have widened in recent years to cover new issues; for example, foreign direct investment rules, policies to promote competition, the international movement of labor, the environment and monetary union. In these negotiations, a consensus among the parties negotiating is usually lacking and many of these negotiat...

Geometry II - Discrete Differential Geometry

Ecken-und Kantenhöhen Im Tetraeder Vertex-and Edge-altitudes of a Tetrahedron 2 Zum Höhenbegriff Eines Tetraeders

k-visina nekog n-simpleksa siječe njegovu k-stranicu i njoj nasuprotnu stranicu okomito. Tetraedar T ima četiri “vřsne visine” (k = 0) i tri “bridne visine” (k = 1). Visine oba tipa izvodnice su posebnih hiperboloida povezanih s tetraedrom T . Članak obrad-uje te hiperboloide na način nacrtne geometrije i daje sintetičke dokaze nekih dobro poznatih svojstava. Pokazuje se, na primjer, da ako se ...

Ein allgemeines, ein semi-orthozentrisches und ein orthozentrisches Tetraeder. Die Höhen eines nicht orthozentrischen Tetraeders liegen auf einer Quadrik. Literaturhinweis:

Aus den Rezensionen: This is a very well written survey of some topics in the geometry of the tetrahedron. Although the subject belongs to that 19th century monument that has been systematically neglected called oldfashioned geometry, the method of solution employed throughout the paper is that of linear algebra, and the paper can be read as making a brilliant point for the teaching of linear a...