Graph Theory: 58. Euler's Formula for Plane Graphs 

In a connected plane graph with n vertices, m edges and r regions, Euler's Formula says that n-m+r=2. In this video we try out a few examples and then prove this fact by induction. We discuss a generalization to disconnected plane graphs as well as what Euler's Formula means for a polyhedron.
-- Bits of Graph Theory by Dr. Sarada Herke.
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"Spoonful of Maths" - / spoonfulofmaths
Video Production by: Giuseppe Geracitano (goo.gl/O8TURb)