Euler polyhedron formula
The Euler polyhedron formula relates the number of faces, edges, and vertices of any polygon or planar graph. The formula is
\[V-E+F=2\]
where \(V\) is the number of vertices, \(E\) is the number of edges, and \(F\) is the number of faces. For example, a cube has 8 vertices, 12 edges, and 6 faces.
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Figure 1: The cube.
and \(8-12+6=2\).