Nikolai Lobachevsky (1792 -1856)

Russian mathematician who has been called the Copernicus of Geometry. His crowning achievement was the development of a non-Euclidean geometry. Lobachevsky replaced Euclid’s fifth postulate, which stated that for any given line and a point not on the line, there is one parallel line through the point not intersecting the line, with one that stated, for any given line and a point not on the line, there is more than one parallel line through the point not intersecting the line.


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Russia, 1 Rubble, 1992