Geometry of circles and polygons.

AI Thread Summary
An equation has been proposed for calculating the perimeter of regular polygons that are tangentially touching circles, expressed as P=Dn*tan(180/n), where P is the perimeter, D is the circle's diameter, and n is the number of polygon sides. The original intent was to approximate pi, but doubts arose regarding its utility for that purpose. The discussion highlights the challenge of computing the tangent function accurately, especially in the context of using calculators. While the equation may not serve to approximate pi, it sparked mathematical curiosity among participants. The potential for alternative applications of the equation remains uncertain.
JDude13
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I have found an equation which deals with regular polygons touching circles tangentially with each of their sides.

P=Dn\tan(\frac{180}{n})
where
P is the perimeter of the polygon.
D is the diameter of the circle.
n is the number of sides on the polygon.

i originaly thought it would be useful for approximating pi but now I am not sure it has a use.

Tell me what you think.
 
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Depends partly on how you planned to compute the tangent function.
 
Umm... I am in yr 11
degrees, i guess. Should i have specified that? I couldn't figure out how to put the degrees sign in LaTeX.
 
I guess what was trying to say is that actually computing tan x is the trick. If you can already do it with, say, a calculator, then you don't really need to "approximate" pi! :)
 
olivermsun said:
I guess what was trying to say is that actually computing tan x is the trick. If you can already do it with, say, a calculator, then you don't really need to "approximate" pi! :)

do you mean that because I am using a calculator that i may as well just go
\pi=
?
I guess youre right.
But since its not used for approximating pi, at least it fueled my mathematic curiosity for 15 mins :P
Maybe it has a use somewhere else... :/
 
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