Pentagon (EntityTopic, 12)

From Hi.gher. Space

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*The [[hypervolume]]s of a pentagon with side length ''l'' are given by:
*The [[hypervolume]]s of a pentagon with side length ''l'' are given by:
<blockquote>total edge length = 5''l''<br>
<blockquote>total edge length = 5''l''<br>
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surface area = {{Over|1|4}} &middot; √(25+10√5) {{DotHV}}</blockquote>
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area = {{Over|1|4}} &middot; √(25+10√5) {{DotHV}}</blockquote>
== Use ==
== Use ==

Revision as of 22:47, 4 February 2014


The pentagon can be seen as the two-dimensional analog to the dodecahedron in 3D and the cosmochoron in 4D. It is also the lowest-dimensional member of the ursatopes, with a (trivial) digonal base.

Equations

  • The hypervolumes of a pentagon with side length l are given by:
total edge length = 5l
area = 14 · √(25+10√5) · l2

Use

Pentagonal faces are found in these trishapes on FGwiki:


Notable Dishapes
Flat: trianglesquarepentagonhexagonoctagondecagon
Curved: circle