2. For example, there were several kinds of plus signs in the past, and the "+"sign was commonly used in modern mathematics. "+"comes from Lavin "et" (meaning "harmony"). /kloc-in the 6th century, Italian scientist Nicolo Tartaglia used the first letter of Italian word "plu" (meaning "add") to indicate addition, and the grass was "μ", which finally became "+". The number "-"is derived from the Latin word "minus" (meaning "minus"). At first, it was abbreviated as m, but later it was simplified to "-"because of its fast writing.
It is also said that wine merchants use "-"to indicate how much a barrel of wine costs. After the new wine is poured into the vat, a vertical line is added to the "-",which means that the original line is erased, thus becoming a "+"sign.
4./kloc-In the 5th century, German mathematician Wei Demei officially determined that "+"was used as a plus sign and "-"was used as a minus sign.
Multiplication has been used for more than a dozen times, and there are two kinds commonly used in modern mathematics. One is "x", which was first proposed by British mathematician orcutt on 163 1; One is "",which was first created by British mathematician heriott. Leibniz, a German mathematician, thinks that "×", like the Latin letter "X", may cause confusion and opposes the use of "×" (in fact, point multiplication is also easily confused with decimal point in some cases). Later, he also proposed to use "∩" to represent multiplication. This symbol has been applied to set theory in modern times.
6./kloc-In the 8th century, American mathematician Audley decided to use "X" as the multiplication sign. He believes that "×" is the rotational deformation of "+"and another symbol of addition.
7. "Dash" was originally used as a negative sign and has been popular in continental Europe for a long time. Until 163 1 year, the British mathematician Orkut used ":"to represent division or ratio, while others used "-"(except lines) to represent division. Later, the Swiss mathematician Laha, in his book Algebra, formally took 圙 as a division symbol according to the creation of the masses.
8. The square root number was once expressed by combining the first and last letters of Latin "root". /kloc-At the beginning of the 0/7th century, the French mathematician Descartes used "√" for the first time in his Geometry. "√" is a variant of Latin word line "R", and "~" is a line enclosed.
9./kloc-In the 6th century, the French mathematician Viette used "=" to indicate the difference between two quantities. However, Calder, a professor of mathematics and rhetoric at Oxford University in England, thinks that it is most appropriate to use two parallel and equal straight lines to indicate that two numbers are equal, so the equal sign "=" has been used since 1540.
10, 159 1 year, the French mathematician Veda used this symbol extensively in diamonds, and it was gradually accepted by people. /kloc-In the 7th century, Leibniz in Germany widely used the symbol "=", and he also used "∽" to indicate similarity and ""to indicate congruence in geometry.
1 1, greater than sign ">" and less than sign "