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Subject: "concerning pi"     Previous Topic | Next Topic
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Lloyd Marks
guest
Aug-03-08, 05:58 PM (EST)
 
"concerning pi"
 
   I think I found an accurate method that converts the area of a circle into a square using only compass and straight edge. All I need to know is if the value 22/7 is an accurate value to use for pi.


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alexb
Charter Member
2314 posts
Aug-03-08, 05:59 PM (EST)
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1. "RE: concerning pi"
In response to message #0
 
   22/7 is a mere approximation to π, albeit reasonably good.


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Anonymous
guest
Aug-15-08, 10:51 AM (EST)
 
2. "RE: concerning pi"
In response to message #0
 
   22/7 is off by about infinity decimal places. I suggest using a better approximation.


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Douglas Ort
guest
Aug-22-08, 08:21 AM (EST)
 
3. "RE: concerning pi"
In response to message #0
 
   Why do people try to do the impossible? If you could "square the (unit) circle", you would have a square with side length the square root of pi. It's a well known theorem that any length that can be constructed from a segment of unit length with ruler and compass is an algebraic number. Consequently, the square root of pi, hence pi itself, would be an algebraic number, contrary to the well known theorem that pi is transcendental.
As far as constructing a square which is "approximately" that of a circle, it is hardly a daunting problem. You can construct a square as close to the circle's area as you wish. Just use a binary approximation to the square root of pi to any accuracy you wish, construct a segment of that length and erect a square on it.


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alexb
Charter Member
2314 posts
Aug-22-08, 08:25 AM (EST)
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5. "RE: concerning pi"
In response to message #3
 
   > Why do people try to do the impossible?
It's a good question. But there are always some people trying. If you are curious, there is a book by Underwood Dudley, Mathematical Cranks, with many many examples.


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parahacker
Member since Jul-10-08
Dec-12-08, 03:34 PM (EST)
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6. "RE: concerning pi"
In response to message #3
 
   >Why do people try to do the impossible?

Gödel showed that even the Principia Mathmatica tried to do something impossible. But if the authors hadn't tried then we'd have missed out on some amazing possible things, I think.

---------------------------------
Embracing self-contradiction since 2006


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