A synthetic proof and generalization of Bellavitis' theorem - Nikolaos Dergiades In this note we give a synthetic proof of Bellavitis' theorem and then generalizing this theorem, for not only convex quadrilaterals, we give a synthetic geometric proof for both theorems direct and converse, as Eisso Atzema proved, by trigonometry, for the convex case (E. J. Atzema, Forum Geom, 6 (2006) 181--185). From this approach evolves clearly the connection between hypothesis and conclusion. ✪ ✪ ✪ ✪ ✪ Link tải tài liệu: LINK TẢI TÀI LIỆU Theo LTTK Education
