French mathematician Soso used some symbols in his three arithmetic papers written in 1484, such as D for addition and M for subtraction. These two symbols first appeared in the commercial speed algorithm written by German mathematician Weidemann. He used "+"for excess and "-"for deficiency. Pass 1565438+. 1544, German mathematician Steefel officially used "+"and "-"to represent addition and subtraction in integer arithmetic, and these two symbols were gradually recognized as real arithmetic symbols. It is widely used. Oughtred, a British mathematician, pioneered the symbol "×". He introduced this symbol in Key to Mathematics published in 163 1 year. It is said that it is derived from the addition symbol+because the multiplication operation is developed from the addition operation of the same number. Later, Leibniz thought that "x" was easily confused with "x". ""it's also approved. The division symbol "∫" was first used in Varis, England, and later popularized in England. In addition to the original meaning of division, the horizontal line in the middle of the symbol "⊙" also separates the upper and lower parts, vividly expressing "division". At this point, the four operation symbols were completed, which was far from being widely adopted by all countries at that time.