On multiplicity of quadrilaterals
نویسندگان
چکیده
منابع مشابه
Spectral method on quadrilaterals
In this paper, we investigate the spectral method on quadrilaterals. We introduce an orthogonal family of functions induced by Legendre polynomials, and establish some results on the corresponding orthogonal approximation. These results play important roles in the spectral method for partial differential equations defined on quadrilaterals. As examples of applications, we provide spectral schem...
متن کاملOn conformal moduli of polygonal quadrilaterals
The change of conformal moduli of polygonal quadrilaterals under some geometric transformations is studied. We consider the motion of one vertex when the other vertices remain fixed, the rotation of sides, polarization, symmetrization, and averaging transformation of the quadrilaterals. Some open problems are formulated. 2000 Mathematics Subject Classification. Primary 30C85. Secondary 30C75.
متن کاملCharacterizations of Orthodiagonal Quadrilaterals
We prove ten necessary and sufficient conditions for a convex quadrilateral to have perpendicular diagonals. One of these is a quite new eight point circle theorem and three of them are metric conditions concerning the nonoverlapping triangles formed by the diagonals. 1. A well known characterization An orthodiagonal quadrilateral is a convex quadrilateral with perpendicular diagonals. The most...
متن کاملProperties of Equidiagonal Quadrilaterals
We prove eight necessary and sufficient conditions for a convex quadrilateral to have congruent diagonals, and one dual connection between equidiagonal and orthodiagonal quadrilaterals. Quadrilaterals with both congruent and perpendicular diagonals are also discussed, including a proposal for what they may be called and how to calculate their area in several ways. Finally we derive a cubic equa...
متن کاملOn some Ramsey Numbers for Quadrilaterals
We will prove that R(C4, C4,K4 − e) = 16. This fills one of the gaps in the tables presented in a 1996 paper by Arste et al. Moreover by using computer methods we improve lower and upper bounds for some other multicolor Ramsey numbers involving quadrilateral C4. We consider 3 and 4-color numbers, our results improve known bounds.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: AKCE International Journal of Graphs and Combinatorics
سال: 2015
ISSN: 0972-8600,2543-3474
DOI: 10.1016/j.akcej.2015.11.018