One of the more famous identities that Euler discovered was the identity relating the five great constants of mathematics: * Euler's number, * pi, * the imaginary unit, * the real unit number, 1 * zero, 0 These five constants of nature, Euler discovered, could neatly be tied together in a single, simple equation: Note that the identity also uses three fundamental operations of arithmetic (as extended to complex numbers): * addition, * multiplication, and * exponentiation. The proof of Euler's identity is trivial if one uses the more generalized Euler's formula.