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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: 18,223
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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'
'You have made another human being happy. There is no greater accomplishment.' -bobbym

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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.


igloo myrtilles fourmis

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

Agnishom
Real Member
From: The Complex Plane
Registered: 2011-01-29
Posts: 18,223
Website

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 have made another human being happy. There is no greater accomplishment.' -bobbym

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