圓周率的英文名稱是什麼?

圓周率，一般以π來表示，是一個在數學及物理學普遍存在的數學常數。它定義為圓形之周長與直徑之比。它也等於圓形之面積與半徑平方之比。是精確計算圓周長、圓面積、球體積等幾何形狀的關鍵。分析學上，π 可定義為是最小的 x > 0 使得 sin(x) = 0。

常用的 π 10進位近以值為3.1415926，另外還有由祖沖之給出的疏率：及密率：。

精確到小數點後第100位的圓周率值

π = 3. 1415926535 8979323846 2643383279 5028841971 6939937510 5820974944 5923078164 0628620899 8628034825 3421170679……

Pi

This article is about the number. For the Greek letter, see pi (letter). For other uses, see Pi (disambiguation).
When a circle's diameter is 1, its circumference is π.The mathematical constant π is an irrational real number, approximately equal to 3.14159, which is the ratio of a circle's circumference to its diameter in Euclidean geometry, and has many uses in mathematics, physics, and engineering. It is also known as Archimedes' constant (not to be confused with an Archimedes number) and as Ludolph's number.

Ratio of the circumference of a circle to its diameter(π/ pi)

圓周率的英文名稱咪 Pi 囉

circumference