Question

Is `pi` a rational number?

Answer 1

No, `pi` is irrational.

Explanation:

`pi` is an irrational number.

The only proofs I have found so far use calculus level mathematics. If I find a simpler one I may reproduce it here.

There are some useful rational approximations for `pi`. You have probably encountered `22/7 = 3.bar(142857)`, but a much better one is `355/113 ~~ 3.1415929`

From memory, the first few decimal places of `pi` are:

`3.141592653589793238462643383279502884196`