Question mark is an auxiliary symbol tool of mood and intonation, which indicates the pause and mood after a sentence is finished. Used at the end of questions, rhetorical questions and rhetorical questions. Pause at the end of the question, with a question mark. A rhetorical question also ends with a question mark. Question marks generally do not appear at the beginning of a line. There are rhetorical questions and rhetorical questions.
The development of mathematical symbols;
For example, 1 used to have several plus signs, and the "+"sign is 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, then "μ", and finally they all became "+". The number "-"is derived from the Latin word "minus" (meaning "minus"). It was abbreviated to M at first, but later it was simplified to "-"because it was written quickly.
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. /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 modern mathematics generally uses two kinds. 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. He opposes it and agrees to use "×".