Pi - Proof that Pi is Irrational - Applied Cryptography Group | Stanford University
Proof that Pi is Irrational Suppose $\pi = a/b$. Define \[f(x)=\frac{x^n(a-bx)^n}{n!}\] and \[F(x) = f(x) - f^{(2)}(x) + f^{(4)}(x) - ... + (-1)^n f^{(2n)}(x)\] for every positive integer $n$. First note that $f(x)$ and its derivat...