Pedal polygons - Daniela Ferrarello, Maria Flavia Mammana and Mario Pennisi We study the pedal polygon H1H2...Hn of a point P with respect to a polygon P, where the points Hi are the feet of the perpendiculars drawn from P to the sides of P. In particular we prove that if P is a quadrilateral which is not a parallelogram, there exists one and only one point P for which the points Hi are collinear. ✪ ✪ ✪ ✪ ✪ Link tải tài liệu: LINK TẢI TÀI LIỆU Theo LTTK Education
