**Vashchenko-Zakharchenko, Mykhailo** [Ващенко-Захарченко, Михайло; Vaščenko-Zaxarčenko, Myxajlo], b 12 November 1825 in Maliivka, Zolotonosha county, Poltava gubernia, d 27 August 1912 in Kyiv. Mathematician. After studying at Kyiv University, the Sorbonne, and the Collège de France (1847–8) he graduated from Kazan University in 1854 and taught at the Kyiv Cadet School (1855–62) and Kyiv University (1863–1902). Vashchenko-Zakharchenko made significant contributions to the theory of linear differential equations, operational calculus, theory of probability, and the history of mathematics. His master’s dissertation was the first treatise in Russian on the operational method and its application to the solution of linear differential equations (1862). He wrote a monograph on the history of mathematics to the 15th century (1883) and a historical survey of the development of analytic geometry. He was the author of 12 textbooks in various fields of mathematics. As one of the first proponents of non-Euclidean geometry in the Russian Empire, he exerted considerable influence on the development of mathematics in Ukraine and Russia.

[This article originally appeared in the *Encyclopedia of Ukraine*, vol. 5 (1993).]