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=__Pi! The Number! __=

__What is π?__
Pi began as the 16th letter in the Greek alphabet, and looked like this: π. Now, we know pi as the circle's circumference. Pi is one of the most important mathematical equations used in science and engineering. Pi, as a decimal, looks like this: 3.14159265358979323846... Notice the. after the last numeral. That indicates that pi is an irrational number. That means that it does not have determined ending, and also that the numbers follow no certain pattern. In other words, in Pi, you will never see the same string of numbers twice.

__A brief history of π__
The symbol "π" is originated from the Greek word "περίμετρος" (meaning perimeter). As I have already mentioned, Pi started out as a Greek letter, however many people wondered about how to show an unending decimal like 3.1415926535897932346... So, many people began to associate the letter π with this decimal, and then the circumference of a circle (however, it is still possible to write it as 3.14, but it is more accepted as π). When using pi in problems use the decimal 3.14, it is a shorted version of the never ending number. 3.14 is π rounded to the nearest thousandth.

__Formulas of π__
Pi is used in many different formulas, some of which you might never learn. Here are some examples of π used in formulas. C=Rπ2 C=Dπ

Definitions D= diameter C= circumference π=pi, 3.14

**__Odd Facts About Pi!__**
Did you know that there is a Pi day? Well yes there is. It is March 14 witch is also Einstein's birthday. To learn more about it click on Pi Day! below. Pi was sort of actually discovered by Egyptians and Babylonians about 4,000 years ago. The **symbol** pi was first introduced by William Jones. Isn't it crazy that this man started this whole thing, I mean look at pi now! There is actually a Pi movie called Pi; The Movie. Pi is now the crazy number.

__Find your Birthday!__
Pi is such a large number, you may find your birthday in it. See how [|here.]

__Links__
[|Wikipedia Pi Page] [|Pi Formula Page] [|Ask Dr.Math About Pi] [|Pi Day!] [|Planet Math About Pi] [|The Pi Trivia Game] [|Pi Land; About Pi] [|Mister Teacher on Pi]

__Pi Songs__
[|Pi Song on How Pi Started] [|Kids Talk About Pi]

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