Pi
From Wikipedia, a free encyclopedia written in simple English for easy reading.
- The title of this article is not totally correct because of some limits Wikipedia has. The correct ways to write the title of this article are either pi (with the lowercase "p") or π.
pi is the number found when the distance around a circle (the circumference) is divided by the distance between opposite ends of the circle (the diameter). Pi is about 3.14159, but 22/7 is close to pi. The number 355/113 is even closer to pi.
Pi is often written as the Greek letter π. Pi is an irrational number, meaning it cannot be written as a fraction (
). However, it is very useful in many ways, not just measuring circles.
Mathematicians have known about pi for thousands of years.
There are different sequences that approximate Pi. Taking 22/7, has an error of about 0.04%. This is sufficient for many applications.
Leibniz' formula for π, due to Gottfried Leibniz, states that
