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#1 2006-02-25 13:43:58
- razor
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- Registered: 2006-02-24
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Pentagram
we have a pentagram.How we can with two lines create nine not covertly triangles?
Last edited by razor (2006-02-25 13:47:57)
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#2 2006-02-25 17:52:53
- MathsIsFun
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Re: Pentagram
I am not sure what "not covertly" means, but my biggest problem is: how is it possible to get nine triangles with only two lines? Best I can do is 5. I can get 9 with three lines!
"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman
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#3 2006-03-01 03:49:49
- ashwil
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- Registered: 2006-02-27
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Re: Pentagram
Trick question!
A pentagram already has 5 triangles within it. Joining any two pairs of alternate nodes on the inner pentagon will create 3 new triangles within the central pentagon and one more with one of the extarnal points. Total 9.
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#4 2006-03-01 03:53:24
- ashwil
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Re: Pentagram
Scrub that last post! That method actually creates 12 triangles!!
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#5 2006-03-01 04:24:37
- krassi_holmz
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- Registered: 2005-12-02
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Re: Pentagram
Here's what I get:
Last edited by krassi_holmz (2006-03-01 04:25:35)
IPBLE: Increasing Performance By Lowering Expectations.
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#6 2006-03-01 08:38:17
- MathsIsFun
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Re: Pentagram
Pentagram ... I should read more careully!
"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman
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#7 2006-03-01 10:05:42
- mathsyperson
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- Registered: 2005-06-22
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Re: Pentagram
I agree with what krazzi has.
Why did the vector cross the road?
It wanted to be normal.
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#8 2006-03-01 17:34:04
- krassi_holmz
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- Registered: 2005-12-02
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Re: Pentagram
Now the other main question: are there another combinations?
For which numbers it is possible to cut the pentagram(or we may start with circle) with k lines?
Hm... Interesting.
IPBLE: Increasing Performance By Lowering Expectations.
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