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Subject: "how do we construct golden triangles?"     Previous Topic | Next Topic
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Conferences The CTK Exchange College math Topic #697
Reading Topic #697
shane
guest
 Oct-07-08, 09:44 PM (EST)
 
"how do we construct golden triangles?"
 
   i find golden triangles interesting. i want to study them closely.
sadly, i can't construct one cause all i know is the angular measurement of these golden triangles.

how can i find the side measurement of a golden triangle? is there a formula for it? i want to sketch golden triangles in my graphing paper, but i just cant get it...

hope you can help me


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alexb
Charter Member
2289 posts		 Oct-07-08, 11:32 PM (EST)
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2. "RE: how do we construct golden triangles?"
In response to message #0
 
   There are actually two triangle that compete for the title of "golden."
36-36-108 and 72-72-36

Assume it's the latter you have in mind.

In this triangle, if the base is 2 units, the side equals

1/sin(18°).

You can verify that sin(18°) = (√5 - 1)/4,

See

https://www.cut-the-knot.org/pythagoras/cos36.shtml


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