Michael Stifel, German mathematician, was born in 1486 and died in 1567. He has done research in arithmetic and algebra. He invented the logarithms independently of Napier, using entirely different approximations from those used by him. His best known work is Arithmetica integrates, published in 1544. In the first part of this work, Stifel highlights the advantages of making the association between an arithmetic progression and a geometric progression, a century before the invention of logarithms. It also presented the coefficients of binomial development up to the seventeenth order. Stifel already used the signs and represented the unknowns many times by letters.
Stifel was raised by the church, studied at the University of Wittenberg. He entered the Augustinian monastery in Esslingen and was ordained in 1511. He was expelled from the monastery in 1522 because he believed that the church somehow withheld money from the poor. He sought refuge with Lutherans and lived in Luther's own house for a time. Luther got a pastoral position for Stifel, but he made the mistake of wanting to “foresee” the end of the world. When they realized he was wrong, he was arrested and fired from his post.
In 1535 he moved to a parish in Holzdorf, and remained there for 12 years. In 1547 Stifel went to Prussia. While there, he taught mathematics and theology at the University of Königsberg, returning three years later to Saxony. In 1559 Stifel obtained a position at the University of Jena, where he taught arithmetic and geometry, although his research was on arithmetic and algebra. He invented logarithms independently of Napier using a totally different approach. His most famous work, "Arithmetic in Integra", was published in 1544 while in Holzdorf.
He also created a rule for Newton's binomial that mentioned that "the sum of two binomial numbers of the same numerator and consecutive denominators is a binominal number whose numerator has one more unit than the numerators of the parcels and the denominator is the largest of the denominators of the parcels. installments ". This rule became known as Stifel Ratio.