Nikolai Lobachevsky

Nikolai Ivanovich Lobachevsky was a Russian mathematician and geometer, born in 1792 and dying in 1856, known primarily for his work on hyperbolic geometry, otherwise known as Lobachevskian geometry, and also for his fundamental study of Dirichlet integrals, known as the Lobachevsky integral formula. At Kazan University he was influenced by professor Johann Christian Martin Bartels, a former teacher and friend of the German mathematician Carl Friedrich Gauss. He became a lecturer at Kazan University in 1814 and an associate professor in 1816, and in 1822, at the age of thirty, he became a full professor, teaching mathematics, physics and astronomy.