Definition of Pi
Pi (π) is a mathematical constant representing the ratio of a circle's circumference to its diameter. It is an irrational number (infinite non-repeating decimal) and also a transcendental number (cannot be the root of any polynomial equation with integer coefficients).
The value of π is approximately 3.14159265358979323846..., and it has wide applications in mathematics, physics, engineering, and other fields.
History of Pi Exploration
Ancient Period
Ancient Egyptians used (16/9)²≈3.1605 as an approximation of π, while Babylonians used 25/8=3.125.
Archimedes
In 250 BCE, Archimedes calculated π between 3.1408 and 3.1429 using the polygon approximation method.
Zu Chongzhi
In 480 CE, Zu Chongzhi calculated π between 3.1415926 and 3.1415927, holding the record for nearly a millennium.
Modern Calculation
In 1706, William Jones first used the π symbol, which was popularized by Euler. π was calculated to 100 decimal places in the 18th century.
Computer Era
In 1949, π was first calculated to 2037 digits by computer. Today, it has been computed to trillions of digits.
World Record
In 2021, Swiss scientists calculated π to 62.8 trillion digits, taking 108 days and 9 hours.
Value of Pi
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