MacTutor
Mathematicians Of The Day
15th April
On this day in 1831 Gauss introduces the term "complex" for a + bi. Most of the 17th and 18th century writers spoke of a + bi as an imaginary quantity. Gauss saw the desirability of having different names for ai and a + bi, so he gave to the latter the Latin expression numeros integros complexos.
See THIS LINK.
On this day in 2013 Google released an Euler doodle.
The postage stamp of one of today's mathematicians at THIS LINK was issued in 1938.
See THIS LINK.
On this day in 2013 Google released an Euler doodle.
The postage stamp of one of today's mathematicians at THIS LINK was issued in 1938.
Click on Ⓟ for a poster.
Born:
- 1452: Leonardo da Vinci Ⓟ
- 1552: Pietro Cataldi
- 1707: Leonhard Euler Ⓟ
- 1809: Hermann Grassmann Ⓟ
- 1886: Aurel Angelescu Ⓟ
- 1921: Maurício Peixoto Ⓟ
- 1923: Enrico Magenes Ⓟ
- 1928: Paul Butzer Ⓟ
- 1929: Brooke Benjamin Ⓟ
- 1932: John Lewis Ⓟ
- 1934: James Wiegold Ⓟ
Died:
- 1446: Filippo Brunelleschi Ⓟ
- 1704: Johann Hudde Ⓟ
- 1754: Jacopo Riccati Ⓟ
- 1878: James Booth Ⓟ
- 1934: George Moffat
- 1983: Vera Nikolaevna Faddeeva Ⓟ
- 1985: Lazar Matveevich Gluskin Ⓟ
- 1990: Karl Heinrich Weise Ⓟ
- 1997: Eugene Graham
- 1999: Floyd Burton Jones Ⓟ
- 2007: Leslie Woods Ⓟ
- 2018: George Oster Ⓟ
Quotation of the day
From Leonhard Euler
Notable enough, however, are the controversies over the series 1 - 1 + 1 - 1 + 1 - ... whose sum was given by Leibniz as , although others disagree. ... Understanding of this question is to be sought in the word "sum"; this idea, if thus conceived -- namely, the sum of a series is said to be that quantity to which it is brought closer as more terms of the series are taken -- has relevance only for convergent series, and we should in general give up the idea of sum for divergent series.
