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【教学片断】本节课前20分钟进行小组交流讨论,完成新授部分后揭示结论:两个数的和同一个数相乘,可以用这两个加数分别同这个数相乘,再把它们的积相加,结果不变。师:这就是乘法的第三个运算定律“乘法分配律”。如果老师用a、b、c表示两个加数和乘数,你能用字母表示乘法分配律吗?
【Teaching Piece】 This lesson 20 minutes before the group exchange and discussion, after the completion of the new part revealed the conclusion: the two numbers multiplied by the same number, you can use the two multiples were multiplied with this number, and then Their products add up, the result remains unchanged. Teacher: This is the third law of multiplication “multiplication assignment ”. If the teacher uses a, b, c to represent two addends and multipliers, can you use the letters to express the multiplicative distribution law?