Pyramid
A Polyhedron with one face a Polygon and all the other faces Triangles with a commonVertex. An 
-gonal regular pyramid (denoted 
) has EquilateralTriangles, and is possible only for 
, 4, 5. These correspond to the Tetrahedron,Square Pyramid, and Pentagonal Pyramid, respectively. A pyramid therefore has a single cross-sectional shape inwhich the length scale of the Cross-Section scales linearly with height. The Area at a height 
is given by
 | (1) |
is the base Area and 
is the pyramid height. The Volume is therefore given by | (2) |
The Centroid is the same as for the Cone, given by
 | (3) |
 | (4) |
is the Slant Height and 
is the base Perimeter. Joining two Pyramids together attheir bases gives a Bipyramid, also called a Dipyramid.See also Bipyramid, Elongated Pyramid, Gyroelongated Pyramid, Pentagonal Pyramid, Pyramid, PyramidalFrustum, Square Pyramid, Tetrahedron, Truncated Square Pyramid
References
Beyer, W. H. (Ed.) CRC Standard Mathematical Tables, 28th ed. Boca Raton, FL: CRC Press, p. 128, 1987. Hart, G. W. ``Pyramids, Dipyramids, and Trapezohedra.'' http://www.li.net/~george/virtual-polyhedra/pyramids-info.html.
- Schauder Fixed Point Theorem
- Scheme
- Schensted Correspondence
- Scherk's Minimal Surfaces
- Schiffler Point
- Schinzel Circle
- Schinzel's Hypothesis
- Schinzel's Theorem
- Schisma
- Schlegel Graph
- Schläfli Double Six
- Schläfli Function
- Schläfli Integral
- Schläfli Polynomial
- Schläfli's Formula
- Schläfli's Modular Form
- Schläfli Symbol
- Schlömilch's Function
- Schlömilch's Series
- Schmitt-Conway Biprism
- Schnirelmann Constant
- Schnirelmann Density
- Schnirelmann's Theorem
- Schoenemann's Theorem
- Scholz Conjecture