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

Agnishom
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From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,835
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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'
I'm not crazy, my mother had me tested.

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## #2 2013-05-13 15:39:44

John E. Franklin
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Registered: 2005-08-29
Posts: 3,588

### 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: Riemann Sphere
Registered: 2011-01-29
Posts: 24,835
Website

### Re: Dots and Lines

Ricky? 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'
I'm not crazy, my mother had me tested.

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