Number pi

Today I‘m going to talk about the number pi. We’re all familiar with this number from early age since the first time our teachers introduced us to it and taught us how to find out circle's circumference. But, have you ever thought what it meant, how the number pi changed the concept of mathematics or how it is used in our daily life? I bet none of you ever considered any of those questions. So today I’ll be talking about all of those things. I‘ll begin by giving you an overview of the number pi’s fundamentals, then I’ll go on to talk about its history and origins and finally I’ll introduce you to its use and give some interesting facts about this extraordinary number.

Firstly, let me fill you in on the concept of the number pi. The number π is a mathematical constant, the ratio of a circle's circumference to its diameter. The symbol used by mathematicians to represent this number is the lowercase Greek letter π, sometimes spelled out as pi, and derived from the first letter of the Greek word perimetros, meaning circumference. As I mentioned before π is commonly defined as the ratio of circle‘s circumference C to its diameter d: π=C/d. The ratio C/d is constant, regardless of the circle's size. For example, if a circle has twice the diameter of another circle it will also have twice the circumference, preserving the ratio C/d.