已知
.求证:
三点共线的充要条件是
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c39d023fc87895b0f26477e890074e3a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7358ff8d99126de46113bb1c1c50f726.png)
更新时间:2020-06-26 10:56:58
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【推荐1】已知
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