论文部分内容阅读
在小学低年级学生刚刚学习乘法时,乘法的概念是这样表述的:“求几个相同加数的和,用乘法计算比较简便。”被乘数表示相同加数,乘数表示相同加数的个数,积表示相同加数的和。根据乘法这一意义,被乘数和乘数均有其固定的含义。在列算式时,它们的位置不能随便移动。如果移动,则表达的意义也随着发生了变化。例如,5×3表示3个5连加,3×5表示5个3连加。但是,由于数范围的不断扩大,乘法的意义也跟着发生变化。例如106×1.25=132.5,2/3×4/5=8/(15)象这样的小数乘法和分数乘法,已经不再表示“求几个相同加数的和”的意义了,而是表
The concept of multiplication is expressed in terms of the multiplication when a student in lower elementary grades has just learned multiplication: “Find the sum of several equal addends, which is easier to calculate by multiplication.” Multiplicands represent the same addend, multipliers denote the same addend The number, the product of the same sum of sums. According to the meaning of multiplication, multiplicands and multipliers have their fixed meanings. When formulating formulas, their positions can not be moved easily. If you move, the meaning of expression also changes. For example, 5 × 3 means 3 5 plus, 3 × 5 means 5 3 plus. However, the significance of multiplication changes with the continuous expansion of the number range. For example, 106 × 1.25 = 132.5, 2/3 × 4/5 = 8 / (15) The fractional multiplication and fractional multiplication like this no longer means the meaning of “finding the sum of several equal addends”