 Évariste Galois (1832) developed techniques for determining whether a given equation could be solved by radicals, which gave rise to the field of Galois theory.Joseph Liouville (1840) showed that neither "e" nor "e"2 can be a root of an integer quadratic equation, and then established the existence of transcendental numbers; Georg Cantor (1873) extended and greatly simplified this proof.Charles Hermite (1873) first proved that "e" is transcendental, and Ferdinand von Lindemann (1882), showed that is transcendental.