The
value of pi
to 5 decimal places is 3.14159. Pi is an irrational number, so it cannot be expressed as an exact fraction and its decimal representation has no end.
The Greek letter pi was first used to represent the ratio of the circumference of a circle to its diameter in 1709 by mathematician William Jones.

en.wikipedia.org/wiki/Pi

The number π is a mathematical constant, the ratio of a circle's circumference to
its diameter, .... The set of complex numbers at which exp(z) is equal to one is
then an (imaginary) arithm...

www.geom.uiuc.edu/~huberty/math5337/groupe/digits.html

100,000 Digits of Pi Pi Logo.
3.141592653589793238462643383279502884197169399375105820974944592307816406286
...

www.mathsisfun.com/numbers/pi.html

circle radius=1, half circumference=pi. Draw a ... Pi (the symbol is the Greek letter
π) is: ... In fact π is not equal to the ratio of any two numbers, which makes it an ...

www.reference.com/math/pi-equal-d6665d91220058dc

The number Pi, symbolized by a Greek letter, has a constant value that
approximately equals 3.14159. Pi is an irrational number, which means it cannot
be ...

www.piday.org/million/

One Million Digits of Pi. 3.14... more digits loading... Pi Clock ... Pi Sightings:
Great Pi Day Activities for Teachers · pi-is-delicious · Pi Sightings: Pi Embroidery
...

www.math.utah.edu/~pa/math/pi.html

pi=3.14159 26535 89793 23846 26433 83279 50288 41971 69399 37510
58209 74944 59230 78164 06286 20899 86280 34825 34211 70679 82148
08651 ...

www.livescience.com/29197-what-is-pi.html

Apr 30, 2013 ... Pi equals the circumference divided by the diameter of a circle. Credit: YuryZap ...
There is no exact value, seeing as the number does not end.

www.livescience.com/34132-what-makes-pi-special.html

Aug 9, 2012 ... Pi appears all over math and nature, not just in circles. ... numbers have no
common factor — that they are "relatively prime" — is equal to 6/π<sup>2</sup>.

math.stackexchange.com/questions/17366/why-is-pi-equal-to-3-14159

Jan 13, 2011 ... Why is π equal to 3.14159 … ... Why is this number equal to 3.14159.... ? Why is it
not some ... but "HOW DO WE KNOW that pi = 3.14159...".