Examples
- The cone over a point p of the real line is the interval {p} x .
- The cone over two points {0,1} is a "V" shape with endpoints at {0} and {1}.
- The cone over an interval I of the real line is a filled-in triangle, otherwise known as a 2-simplex (see the final example).
- The cone over a polygon P is a pyramid with base P.
- The cone over a disk is the solid cone of classical geometry (hence the concept's name).
- The cone over a circle is the curved surface of the solid cone:
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- This in turn is homeomorphic to the closed disc.
- In general, the cone over an n-sphere is homeomorphic to the closed (n+1)-ball.
- The cone over an n-simplex is an (n+1)-simplex.
Read more about this topic: Cone (topology)
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