About Karl Weierstrass
Karl Theodor Wilhelm Weierstrass (; German: Weierstraß [ˈvaɪɐʃtʁaːs]; 31 October 1815 – 19 February 1897) was a German mathematician often cited as the "father of modern analysis". Despite leaving university without a degree, he studied mathematics and trained as a school teacher, eventually teaching mathematics, physics, botany and gymnastics. He later received an honorary doctorate and became professor of mathematics in Berlin. Among many other contributions, Weierstrass formalized the definition of the continuity of a function and complex analysis, proved the intermediate value theorem and the Bolzano–Weierstrass theorem, and used the latter to study the properties of continuous functions on closed bounded intervals. Professor Reinhard Bölling discovered the draft of the letter she wrote to Weierstrass when she arrived in Stockholm in 1883 upon her appointment as Privatdocent at Stockholm University. During this period of study, Weierstrass attended the lectures of Christoph Gudermann and became interested in elliptic functions.
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