The Pi FAQ - Answers

1. What is Pi?

Pi is the sum of the infinite series 1 - 1/3 + 1/5 - 1/7 + 1/9 - 1/11... multiplied by 4.

2. How much is Pi, approximately?

The value of Pi varies according to the radius of the circle, so it's hard to tell.

3. Approximating Pi

3.1. How many digits will I have to produce to reach a state of all-zeroes?

It was proven that after a number between 1.345698 and 1.74 times 10 ** 12 digits, Pi is all zeros.

3.2. What is the fastest algorithm for approximating Pi?

Approximating Pi was found to be NP-Complete.

4. What can I do with Pi?

The most common use of Pi is to generate random sequences. A far less common use is for geometrical and trigonometrical calculations.