WEBVTT

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我们现在来看一下分数的除法

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比如说我有负5/6

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除以3/4

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我们已经复习过除法

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这和乘以它的倒数是一样的

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所以，这和负5/6乘以3/4的倒数

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我只是把分子和分母倒一下

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我们已经谈过分数乘法，这次是分子相乘

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所以是-5乘以4。分母上是6乘以3

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现在分子上有一个负数。5乘以4是20

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你只要记住，现在是负数乘以正数

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这里其实有4个-5，等于-20

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所以分子是-20，分母是18

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答案是-20/18，但我们需要简化

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把分子和分母都除以2

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我们把分子和分母都除以2，来简化

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因为2是同时能被分子和分母除的数

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20除以2是10，18除以2是9

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所以5/6除以3/4。。

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