Date: 09/29/2001 at 06:41:58 From: Kate Rogers Subject: Graph Theory Can you please explain to me briefly why a graph with five vertices each having a degree of 3 is not possible ?
Date: 09/30/2001 at 01:16:09 From: Doctor Jodi Subject: Re: Graph Theory Hi Kate, It might help to draw some pictures of small graphs. Degree 3 means that each vertex has three edges coming from it. Notice that each edge connects to exactly two vertices. So how many edges are there, if your graph has five vertices? There should be 3 * 5/2 = 7 1/2 edges. Does this make sense? But of course you can't have half edges, so this is impossible. Write back if you have more questions. - Doctor Jodi, The Math Forum http://mathforum.org/dr.math/
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