Asked by Anonymous

what is the origin of pi? where does it come from? How is it used?


Answered by drwls
Ancient mathematicians noted long ago that the ratio of the circumference to the diameter of a circle was about 3.1416, and that it was an "irrational" number that could not be written exactly as a fraction. Methods were developed to calculate it with arbitrary accuracy by adding up infinite series.

It has many uses in mathematics and physics.

You will enjoy reading more about it here:

http://mathforum.org/dr.math/faq/faq.pi.html