Pentagonum
Pentagonon[1] (Graece πεντάγωνον < πεντα- 'quinque' + γωνία 'angulus'), etiam 5-gon appellatum, in geometria est polygonon quinque angulorum vel laterum. Summa angulorum internorum in pentagono simplice est 540°.
Exempla pentagonorumRecensere
PlantaeRecensere
Transversa Abelmoschi esculenti sectio.
Convolvulaceis, sicut multis floribus aliis, est forma pentagonalis.
Gynoecium mali quinque carpella continet, in stella quinquies punctata ordinata.
Fructui Averrhoae carambolae est symmetria quincuplex.
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AnimaliaRecensere
Oreaster reticulatus. Multis echinodermatibus est symmetria quincuplex radialis.
Aliud echinodermatis exemplum: endosceletus echinoidei.
Adumbratio echinodermatis classis Ophiuroideorum.
MineraliaRecensere
Quasicrystallum Ho-Mg-Zn, ut dodecahedron pentagonale formatum Facies sunt vera pentagona regularia.
Crystallum pyritohedrale pyritis. Pyritohedrono est duodecim eaedem facies pentagonales, quae autem regulares non necesse sunt.
Res artificiosaeRecensere
Pentagonon, praetorium United States Department of Defense.
Pentagona in polyhedraRecensere
| Ih | Th | Td | O | I | D5d |
|---|---|---|---|---|---|
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| Dodecahedron | Pyritohedron | Tetartoidum | Icositetrahedron pentagonale | Hexecontahedron pentagonale | Trapezohedron truncatum |
NotaeRecensere
- ↑ Oxford Latin Dictionary ed. P. G. W. Glare (Oxonii: Clarendon Press, 1968–1982), s.v. "pentagonos."
BibliographiaRecensere
- Buchholz, Ralph H., et James A. MacDougall. 2008. "Cyclic polygons with rational sides and area." Journal of Number Theory 128 (1): 17–48. doi:10.1016/j.jnt.2007.05.005. MR 2382768. Editio interretialis.
- Conway, John H., Heidi Burgiel, et Chaim Goodman-Strauss. 2008. "Generalized Schaefli symbols: Types of symmetry of a polygon." In The Symmetries of Things, capitulum 20, 275–78. ISBN 978-1-56881-220-5.
- Meskhishvili, Mamuka. 2020. "Cyclic Averages of Regular Polygons and Platonic Solids." Communications in Mathematics and Applications 11: 335–55. Editio interretialis.
- Robbins, D. P. 1994. "Areas of Polygons Inscribed in a Circle." Discrete and Computational Geometry 12: 223–36. doi:10.1007/bf02574377.