Leonard Paul Euler (1707 - 1783)

Swiss mathematician often considered one of the greatest m athematicians of all time. He contributed to many areas of mathematics including, but not limited to calculus, analysis, geometry, number theory, graph theory and logic. Euler introduced the f(x) notation for a function and the S notation for a summation. Many results bear his name including Eulerís formula v-e+f=2 for convex polyhedron, Eulerís formula for the complex exponential, e^ix=cos(x)+i sin(x), Euler paths and circuits in graph theory, end even the number e is so in honor of him. He discovered the series expansions for e^x and tan^(-1)(x)? and his use of power series enabled him to determine that SUM(n=1)^8¶?1/n^2 =pi^2/6?.

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