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 pentagonorum
recensere-
Transversa Abelmoschi esculenti sectio.
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Convolvulaceis, sicut multis floribus aliis, est forma pentagonalis.
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Oreaster reticulatus. Multis echinodermatibus est symmetria quincuplex radialis.
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Aliud echinodermatis exemplum: endosceletus echinoidei.
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Adumbratio echinodermatis classis Ophiuroideorum.
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Quasicrystallum Ho-Mg-Zn, ut dodecahedron pentagonale formatum Facies sunt vera pentagona regularia.
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Crystallum pyritohedrale pyritis. Pyritohedrono est duodecim eaedem facies pentagonales, quae autem regulares non necesse sunt.
Res artificiosae
recensere-
Pentagonon, praetorium United States Department of Defense.
Pentagona in polyhedra
recensereIh | Th | Td | O | I | D5d |
---|---|---|---|---|---|
Dodecahedron | Pyritohedron | Tetartoidum | Icositetrahedron pentagonale | Hexecontahedron pentagonale | Trapezohedron truncatum |
Notae
recensere- ↑ Oxford Latin Dictionary ed. P. G. W. Glare (Oxonii: Clarendon Press, 1968–1982), s.v. "pentagonos."
Bibliographia
recensere- 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.