“+”是15世纪德国数学家魏德美创造的。在线上加一竖,表示增加。“-”也是由德国数学魏德美创造的,从加号中减去竖,表示减少。“×”是18世纪美国数家欧稳莱最先创造的,它的意是表示增加的另一种方“÷”是18世纪瑞士人哈纳创造的,表示分解的意思,用一条横线把两个圆点分开。 “+” Was created by German mathematician Wei Demei in the 15th century. Add a vertical line, said the increase. “-” was also created by the German mathematics Wei Demei, subtracting the vertical from the plus sign, indicating a decrease. “X” was first created by several American ounces of the United States in the 18th century. It is intended to mean that the other added square “÷” was created by Hana in the 18th century and represents the meaning of decomposition, with a horizontal line Separate the two dots.