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> | ||
- | + | area = {{Over|1|4}} · √(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 = 1∕4 · √(25+10√5) · l2
Use
Pentagonal faces are found in these trishapes on FGwiki:
- Dodecahedron (12×, 100%)
- Icosidodecahedron (12×, 38%)
- Icosahedral truncate (12×, 38%)
- Dodecahedral snub (12×, 13%)
Notable Dishapes | |
Flat: | triangle • square • pentagon • hexagon • octagon • decagon |
Curved: | circle |