Christoff Rudolff (born 1499 in Jawor, Silesia, died 1545 in Vienna) was the author of the first German textbook on algebra.
Rudolff was from 1517 to 1521 a student of Henricus Grammateus (Schreyber from Erfurt) at the University of Vienna and was the author of a book computing, under the title: Behend und hübsch Rechnung durch die kunstreichen regeln Algebre.
He introduced the radical symbol (√) for the square root. It is believed that this was because it resembled a lowercase "r" (for "radix"), though there is no direct evidence. Cajori only says that a "dot is the embryo of our present symbol for the square root" though it is "possible, perhaps probable" that Rudolff's later symbols are not dots but 'r's.
Furthermore, he used the meaningful definition that x0 = 1.
- ^ a b Walter William Rouse Ball (1960), A short account of the history of mathematics (4 ed.), Courier Dover Publications, p. 215, ISBN 978-0-486-20630-1
- ^ a b Howard Whitley Eves (1983), Great moments in mathematics (before 1650: Volume 1), MAA, p. 131, ISBN 978-0-88385-310-8
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- ^ a b Florian Cajori (1919), A history of mathematics (2 ed.), The Macmillan Company, p. 140
- ^ a b Florian Cajori (1993 (reprint)), A history of mathematical notations, Volumes 1-2, Courier Dover Publications, p. 369, ISBN 978-0-486-67766-8