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January 25th, 2019, 08:15 AM   #1
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Calculating Pi for fun.

Hello,

So, I was doing the following equation for fun:

(5/2)r^2sin(72)

A thought came to my mind I wanted to share.

The more sides a regular polygon has, and the smaller the angles, the closer the answer gets to Pi if r=1.

I thought this because, the more sides and the smaller the angles, the closer it gets to being a circle.

I began to experiment as follows.

(5/2)1^2sin(72)=2.377641291

(36/2)1^2sin(10)=3.12566719

(360/2)1^2sin(1)=3.14143315

(3600/2)1^2sin(0.1)=3.14159105

(36000/2)1^2sin(0.01)=3.14159263

(360000/2)1^2sin(0.001)=3.14159265

And so on.

When I post this kind of stuff, I am NOT trying to be boastful or smart. I just like sharing what I learn.

I just wanted to share this. I hope you enjoyed reading it.

If you have anything you want to add on, feel free to do so.

Happy calculating!

Jared
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January 25th, 2019, 08:37 AM   #2
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Well done. That's the way Pythagoras (I think) worked out his value for $\pi$. You are in good company.
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January 25th, 2019, 09:13 AM   #3
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Quote:
Originally Posted by v8archie View Post
Well done. That's the way Pythagoras (I think) worked out his value for $\pi$. You are in good company.
I think you mean Archimedes.

EDIT:

If I remember correctly, he used inscribed and circumscribed polygons so that he placed upper and lower bounds on the value of pi.
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Last edited by JeffM1; January 25th, 2019 at 09:15 AM.
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January 25th, 2019, 02:23 PM   #4
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Close enough!
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January 25th, 2019, 03:58 PM   #5
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Quote:
Originally Posted by JeffM1 View Post
I think you mean Archimedes.

EDIT:

If I remember correctly, he used inscribed and circumscribed polygons so that he placed upper and lower bounds on the value of pi.
Oh that's right. Pythagoras invented triangles...

-Dan
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January 25th, 2019, 04:23 PM   #6
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Pi is everywhere , i doubt that it hides a lot .

Last edited by idontknow; January 25th, 2019 at 04:26 PM.
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