英文数学符号的读法+ plus　加号；正号- minus　减号；负号　plus or minus　正负号　is multiplied by　乘号　is divided by　除号＝　is equal to　等于号≠　is not equal to　不等于号≡　is equivalent to　全等于号≌　is equal to or approximately equal to　等于或约...