Namespaces
Variants
Actions

Difference between revisions of "Prism"

From Encyclopedia of Mathematics
Jump to: navigation, search
(Importing text file)
 
(TeX)
 
Line 1: Line 1:
A [[Polyhedron|polyhedron]] for which two sides are <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/p/p074/p074830/p0748301.png" />-gons (the bases of the prism), while the other <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/p/p074/p074830/p0748302.png" /> sides (the lateral sides) are parallelograms. The bases are congruent and located in parallel planes. A prism is called direct if the planes of the lateral sides are orthogonal with the planes of the bases. A direct prism is called regular if its bases are [[Regular polyhedra|regular polyhedra]]. A prism is called triangular, rectangular, etc., depending on whether the bases are triangular, rectangular, etc. Six-angled prisms are shown in the figures (Fig. a shows a direct prism). The volume of a prism is equal to the product of the area of one of its bases and its height (the distance between the bases).
+
{{TEX|done}}
 +
A [[Polyhedron|polyhedron]] for which two sides are $n$-gons (the bases of the prism), while the other $n$ sides (the lateral sides) are parallelograms. The bases are congruent and located in parallel planes. A prism is called direct if the planes of the lateral sides are orthogonal with the planes of the bases. A direct prism is called regular if its bases are [[Regular polyhedra|regular polyhedra]]. A prism is called triangular, rectangular, etc., depending on whether the bases are triangular, rectangular, etc. Six-angled prisms are shown in the figures (Fig. a shows a direct prism). The volume of a prism is equal to the product of the area of one of its bases and its height (the distance between the bases).
  
 
<img style="border:1px solid;" src="https://www.encyclopediaofmath.org/legacyimages/common_img/p074830a.gif" />
 
<img style="border:1px solid;" src="https://www.encyclopediaofmath.org/legacyimages/common_img/p074830a.gif" />
Line 12: Line 13:
  
 
====Comments====
 
====Comments====
In <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/p/p074/p074830/p0748303.png" />-space a prism is the vector-sum of a <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/p/p074/p074830/p0748304.png" />-polytope and a segment which is not parallel to the affine hull of the <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/p/p074/p074830/p0748305.png" />-polytope.
+
In $d$-space a prism is the vector-sum of a $(d-1)$-polytope and a segment which is not parallel to the affine hull of the $(d-1)$-polytope.
  
 
====References====
 
====References====
 
<table><TR><TD valign="top">[a1]</TD> <TD valign="top">  B. Grünbaum,  "Convex polytopes" , Wiley  (1967)</TD></TR></table>
 
<table><TR><TD valign="top">[a1]</TD> <TD valign="top">  B. Grünbaum,  "Convex polytopes" , Wiley  (1967)</TD></TR></table>

Latest revision as of 16:31, 11 April 2014

A polyhedron for which two sides are $n$-gons (the bases of the prism), while the other $n$ sides (the lateral sides) are parallelograms. The bases are congruent and located in parallel planes. A prism is called direct if the planes of the lateral sides are orthogonal with the planes of the bases. A direct prism is called regular if its bases are regular polyhedra. A prism is called triangular, rectangular, etc., depending on whether the bases are triangular, rectangular, etc. Six-angled prisms are shown in the figures (Fig. a shows a direct prism). The volume of a prism is equal to the product of the area of one of its bases and its height (the distance between the bases).

Figure: p074830a

Figure: p074830b


Comments

In $d$-space a prism is the vector-sum of a $(d-1)$-polytope and a segment which is not parallel to the affine hull of the $(d-1)$-polytope.

References

[a1] B. Grünbaum, "Convex polytopes" , Wiley (1967)
How to Cite This Entry:
Prism. Encyclopedia of Mathematics. URL: http://encyclopediaofmath.org/index.php?title=Prism&oldid=31510
This article was adapted from an original article by BSE-3 (originator), which appeared in Encyclopedia of Mathematics - ISBN 1402006098. See original article