Leonhard Euler

Euler, Leonhard (1707-83), Swiss mathematician, whose major work was done in the
field of pure mathematics, a field that he helped to found. Euler was born in
Basel and studied at the University of Basel under the Swiss mathematician
Johann Bernoulli, obtaining his master\'s degree at the age of 16. In 1727, at
the invitation of Catherine I, empress of Russia, Euler became a member of the
faculty of the Academy of Sciences in Saint Petersburg. He was appointed
professor of physics in 1730 and professor of mathematics in 1733. In 1741 he
became professor of mathematics at the Berlin Academy of Sciences at the urging
of the Prussian king Frederick the Great. Euler returned to St. Petersburg in
1766, remaining there until his death. Although hampered from his late 20s by
partial loss of vision and in later life by almost total blindness, Euler
produced a number of important mathematical works and hundreds of mathematical
and scientific memoirs.

In his Introduction to the Analysis of Infinities (1748; trans. 1748), Euler
gave the first full analytical treatment of algebra, the theory of equations,
trigonometry, and analytical geometry. In this work he treated the series
expansion of functions and formulated the rule that only convergent infinite
series can properly be evaluated. He also discussed three-dimensional surfaces
and proved that the conic sections are represented by the general equation of
the second degree in two dimensions. Other works dealt with calculus, including
the calculus of variations, number theory, imaginary numbers, and determinate
and indeterminate algebra. Euler, although principally a mathematician, made
contributions to astronomy, mechanics, optics, and acoustics

Category: Science