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Topic: A question about straight lines
Replies: 103   Last Post: Feb 8, 2014 8:28 AM

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Neighbor

Posts: 57
From: It doesn't matter
Registered: 1/26/14
Re: A question about straight lines
Posted: Jan 28, 2014 1:24 PM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

I didn't say that AB is an endless line in both directions, I said that AB is a finite straight-line (having the endpoints A and B), therefore AG and GB in which AB has been divided are also finite straight-lines.
About the "open ray": how can a finite straight-line have no boundary???? Being made of points, there must be two boundaries in both directions, which we call endpoints, for if there is no boundary this is not a finite straight-line but an infinite one.
Therefore I don't understand your notion of "open ray", but if you are willing to explain me this concept in detail and make me understand, I will be grateful.

>
> AB is a line (it extends forever in both directions).
>
> AG is a ray (it has a beginning and extends forever
> in one direction).
>
> What is left (what you are calling GB) is not a line,
> ray or segment. It might be called an ?open ray? due
> to it being an open set of points. An open set of
> points does not include its boundary. A closed set of
> points does. A line, ray and segment are all closed.
>
> http://en.wikipedia.org/wiki/Boundary_(topology)
>
> Bob Hansen



Message was edited by: Neighbor


Date Subject Author
1/26/14
Read A question about straight lines
Neighbor
1/26/14
Read Re: A question about straight lines
kirby urner
1/27/14
Read Re: A question about straight lines
Neighbor
1/27/14
Read Re: A question about straight lines
Robert Hansen
1/27/14
Read Re: A question about straight lines
Bishop, Wayne
1/27/14
Read Re: A question about straight lines
kirby urner
1/27/14
Read Re: A question about straight lines
Neighbor
1/27/14
Read Re: A question about straight lines
Robert Hansen
1/27/14
Read Re: A question about straight lines
Neighbor
1/27/14
Read Re: A question about straight lines
Neighbor
1/28/14
Read Re: A question about straight lines
Neighbor
1/28/14
Read Re: A question about straight lines
Robert Hansen
1/28/14
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Joe Niederberger
1/28/14
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Robert Hansen
1/28/14
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Neighbor
1/28/14
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Robert Hansen
1/28/14
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Joe Niederberger
1/28/14
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Joe Niederberger
1/28/14
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Neighbor
1/28/14
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Robert Hansen
1/28/14
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Joe Niederberger
1/28/14
Read Re: A question about straight lines
Joe Niederberger
1/28/14
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Robert Hansen
1/28/14
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Neighbor
1/28/14
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Gary Tupper
1/28/14
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Robert Hansen
1/28/14
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Joe Niederberger
1/28/14
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Joe Niederberger
1/28/14
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Louis Talman
1/28/14
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Joe Niederberger
1/28/14
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Joe Niederberger
1/28/14
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Joe Niederberger
1/28/14
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Joe Niederberger
1/29/14
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Robert Hansen
1/29/14
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Bishop, Wayne
1/29/14
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GS Chandy
1/29/14
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Domenico Rosa
1/29/14
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Neighbor
1/29/14
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Joe Niederberger
1/29/14
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Neighbor
1/29/14
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Domenico Rosa
1/30/14
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Bishop, Wayne
1/29/14
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Joe Niederberger
1/29/14
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Neighbor
1/29/14
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Robert Hansen
1/29/14
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Joe Niederberger
1/29/14
Read Re: A question about straight lines
Joe Niederberger
1/29/14
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Robert Hansen
1/30/14
Read Re: A question about straight lines
Neighbor
1/29/14
Read Re: A question about straight lines
Robert Hansen
1/29/14
Read Re: A question about straight lines
Joe Niederberger
1/30/14
Read Re: A question about straight lines
Louis Talman
1/29/14
Read Re: A question about straight lines
Joe Niederberger
1/30/14
Read Re: A question about straight lines
Neighbor
1/30/14
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Jonathan Crabtree
1/30/14
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Joe Niederberger
1/30/14
Read Re: A question about straight lines
Joe Niederberger
1/31/14
Read Re: A question about straight lines
kirby urner
1/30/14
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Joe Niederberger
1/31/14
Read Re: A question about straight lines
Neighbor
1/30/14
Read Re: A question about straight lines
Joe Niederberger
1/31/14
Read Re: A question about straight lines
Neighbor
1/31/14
Read Re: A question about straight lines
Robert Hansen
1/31/14
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Joe Niederberger
1/31/14
Read Re: A question about straight lines
Joe Niederberger
1/31/14
Read Re: A question about straight lines
Joe Niederberger
1/31/14
Read Re: A question about straight lines
Joe Niederberger
1/31/14
Read Re: A question about straight lines
Robert Hansen
1/31/14
Read Re: A question about straight lines
Joe Niederberger
1/31/14
Read Re: A question about straight lines
Neighbor
1/31/14
Read Re: A question about straight lines
Robert Hansen
1/31/14
Read Re: A question about straight lines
Joe Niederberger
1/31/14
Read Re: A question about straight lines
Joe Niederberger
1/31/14
Read Re: A question about straight lines
Robert Hansen
1/31/14
Read Re: A question about straight lines
Neighbor
1/31/14
Read Re: A question about straight lines
Robert Hansen
1/31/14
Read Re: A question about straight lines
GS Chandy
1/31/14
Read Re: A question about straight lines
GS Chandy
1/31/14
Read Re: A question about straight lines
GS Chandy
1/31/14
Read Re: A question about straight lines
Joe Niederberger
2/1/14
Read Re: A question about straight lines
GS Chandy
2/1/14
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Robert Hansen
2/1/14
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kirby urner
2/1/14
Read Re: A question about straight lines
Robert Hansen
2/1/14
Read Re: A question about straight lines
Joe Niederberger
2/1/14
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Robert Hansen
2/1/14
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Joe Niederberger
2/2/14
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Robert Hansen
2/2/14
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kirby urner
2/1/14
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Joe Niederberger
2/2/14
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Robert Hansen
2/2/14
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James Elander
2/2/14
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GS Chandy
2/2/14
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Robert Hansen
2/2/14
Read Re: A question about straight lines
GS Chandy
2/2/14
Read Re: A question about straight lines
Robert Hansen
2/2/14
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Joe Niederberger
2/2/14
Read Re: A question about straight lines
GS Chandy
2/2/14
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Robert Hansen
2/2/14
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GS Chandy
2/4/14
Read Re: A question about straight lines
GS Chandy
2/4/14
Read Re: A question about straight lines
GS Chandy
2/4/14
Read Re: A question about straight lines
GS Chandy
2/8/14
Read Re: A question about straight lines
GS Chandy

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