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#1 2013-05-01 17:06:22

Agnishom
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From: The Complex Plane
Registered: 2011-01-29
Posts: 17,159
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Dots and Lines

If G is a regular graph and d, e and v denote the degree, the number of edges and the number of vertices respectively, then e = dv/2.

Prove the above statement


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
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#2 2013-05-13 15:39:44

John E. Franklin
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Registered: 2005-08-29
Posts: 3,562

Re: Dots and Lines

since a line segment or "edge" has two ends, then yes, 1/2 is the formula.  v=dots  d=ends of lines on a dot.   e=#ofline segs
Pretty obvious really if you draw a few.  but to prove it, ask Ricky.


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#3 2013-05-18 02:55:36

Agnishom
Real Member
From: The Complex Plane
Registered: 2011-01-29
Posts: 17,159
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Re: Dots and Lines

Ricky? sad He's gone


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'You made a human being happy! There is no further achievement.' -bobbym

Online

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