如图,在等边
的边上分别取点D,E,F,使
,连接
,
,
.
结论Ⅰ:当
时,
的面积取得最小值;
结论Ⅱ:若点O是
的外心,则它一定也是
的外心.对于结论Ⅰ和Ⅱ,下列判断正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5bcb4e1c3913b81c0096f1a14096d677.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
结论Ⅰ:当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68fbbd17c89f03dbb61cd6ffdb9a0344.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72cb97395ebc5ee1b212afb7a97b985c.png)
结论Ⅱ:若点O是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72cb97395ebc5ee1b212afb7a97b985c.png)
A.Ⅰ和Ⅱ都对 | B.Ⅰ和Ⅱ都不对 |
C.Ⅰ不对Ⅱ对 | D.Ⅰ对Ⅱ不对 |
更新时间:2024-05-13 15:52:01
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