Prismatoid polyhedra

Enneagonal antiprism

In geometry, the enneagonal antiprism (or nonagonal antiprism) is one in an infinite set of convex antiprisms formed by triangle sides and two regular polygon caps, in this case two enneagons. Antiprisms are similar to prisms except the bases are twisted relative to each other, and that the side faces are triangles, rather than quadrilaterals. In the case of a regular 9-sided base, one usually considers the case where its copy is twisted by an angle 180Β°/n. Extra regularity is obtained by the line connecting the base centers being perpendicular to the base planes, making it a right antiprism. As faces, it has the two n-gonal bases and, connecting those bases, 2n isosceles triangles. If faces are all regular, it is a semiregular polyhedron. (Wikipedia).

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What are four types of polygons

πŸ‘‰ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

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What is the difference between convex and concave

πŸ‘‰ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

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Billiard in a 9-pointed star

In yet another attempt to kill YouTube's compression algorithm, this simulation shows 50 000 particles in a billiard shaped like a 9-pointed star. This shape is obtained by adding an inward-curving circular arc to each side of a regular nonagon (or enneagon). The radius of the arcs is chos

From playlist Particles in billiards

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What is the difference between convex and concave polygons

πŸ‘‰ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

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What is a concave polygon

πŸ‘‰ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

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What is the difference between concave and convex polygons

πŸ‘‰ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

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Perfect Shapes in Higher Dimensions - Numberphile

Carlo Sequin talks through platonic solids and regular polytopes in higher dimensions. More links & stuff in full description below ↓↓↓ Extra footage (Hypernom): https://youtu.be/unC0Y3kv0Yk More videos with with Carlo: http://bit.ly/carlo_videos Edit and animation by Pete McPartlan Pete

From playlist Carlo SΓ©quin on Numberphile

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What is a net

πŸ‘‰ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

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What is an equilateral triangle

πŸ‘‰ Learn the essential definitions of triangles. A triangle is a polygon with three sides. Triangles are classified on the basis of their angles or on the basis of their side lengths. The classification of triangles on the bases of their angles are: acute, right and obtuse triangles. The cl

From playlist Types of Triangles and Their Properties

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What are the names of different types of polygons based on the number of sides

πŸ‘‰ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

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Chemistry 107. Inorganic Chemistry. Lecture 22.

UCI Chemistry: Inorganic Chemistry (Fall 2014) Lec 22. Inorganic Chemistry -- Coordination Chemistry I: Coordination Geometries View the complete course: http://ocw.uci.edu/courses/chem_107_inorganic_chemistry.html Instructor: Alan F. Heyduk. License: Creative Commons CC-BY-SA Terms of Us

From playlist Chem 107: Week 8

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What is an equiangular triangle

πŸ‘‰ Learn the essential definitions of triangles. A triangle is a polygon with three sides. Triangles are classified on the basis of their angles or on the basis of their side lengths. The classification of triangles on the bases of their angles are: acute, right and obtuse triangles. The cl

From playlist Types of Triangles and Their Properties

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Thin Groups and Applications - Alex Kontorovich

Analysis and Beyond - Celebrating Jean Bourgain's Work and Impact May 21, 2016 More videos on http://video.ias.edu

From playlist Analysis and Beyond

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Energy minimization by Abhinav Kumar

DISCUSSION MEETING SPHERE PACKING ORGANIZERS: Mahesh Kakde and E.K. Narayanan DATE: 31 October 2019 to 06 November 2019 VENUE: Madhava Lecture Hall, ICTS Bangalore Sphere packing is a centuries-old problem in geometry, with many connections to other branches of mathematics (number the

From playlist Sphere Packing - 2019

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Sketch a net from a 3D figure

πŸ‘‰ Learn about polygons and how to classify them. A polygon is a plane shape bounded by a finite chain of straight lines. A polygon can be concave or convex and it can also be regular or irregular. A concave polygon is a polygon in which at least one of its interior angles is greater than 1

From playlist Classify Polygons

Related pages

Semiregular polyhedron | Polygon | Geometry | Prism (geometry)