Izvorni znanstveni članak
Diagonal triangle of a non-tangential quadrilateral in the isotropic plane
Jelena Beban-Brkić
; aculty of Geodesy, University of Zagreb, Zagreb, Croatia
Marija Šimić
; Faculty of Architecture, University of Zagreb, Zagreb, Croatia
Vladimir Volenec
; Department of Mathematics, University of Zagreb, Zagreb, Croatia
Sažetak
Properties of the non-tangential quadrilateral $\lijepoa \lijepob
\lijepoc \lijepod$ in the isotropic plane concerning its diagonal
triangle are given in this paper. A quadrilateral is called standard
if a parabola with the equation $x=y^2$ is inscribed in it. Every
non-tangential quadrilateral can be represented in the standard
position. First, the vertices and the equations of the sides of the
diagonal triangle are introduced. It is shown that the midlines of
the diagonal triangle touch the inscribed parabola of the
quadrilateral. Furthermore, quadrilaterals formed by two diagonals
and some two sides of the non-tangential quadrilateral $\lijepoa
\lijepob \lijepoc \lijepod$ are studied and a few theorems on its
foci are presented.
Ključne riječi
isotropic plane; non-tangential quadrilateral; diagonal triangle; focus; median
Hrčak ID:
68632
URI
Datum izdavanja:
10.6.2011.
Posjeta: 1.113 *