1 . 给出下列命题:
①命题“若
,则
,
全为
”的否命题是“若
,则
,
全不为
”;
②命题“已知
,若
,则
或
”的逆否命题是真命题;
③设
,则“
或
”是“
”的充分不必要条件;
④已知双曲线
的一条渐近线经过点
,则该双曲线的离心率为
.
其中是真命题的有( )
①命题“若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fb20e291772c2614ad19f4cc919dfec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c95b6be4554f03bf496092f1acdfbb89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a68dbd91d6de68b550a5745ecd461d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c95b6be4554f03bf496092f1acdfbb89.png)
②命题“已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5ab4b75fa22deba7fcbcdcb31dd45b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a34982de5d3f287cd570ea30eb46d185.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8d09b9fc9719ff6faf32254b9d48713.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1be861d83cddb5fc8aa22f7f0f9415d6.png)
③设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5ab4b75fa22deba7fcbcdcb31dd45b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e30c903d8f8a05332af0b19e7e40df3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/515713922221bfa136afa32822bb7ad1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc9745ec0409244fd87cecd954bc0a5e.png)
④已知双曲线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a5ec7fa23be9cbe9a50607ea6bc8a4ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25f114df5ceabdb7e5fd3fdad4eaf056.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2967337e3fcb228dded64ab0c41a17e0.png)
其中是真命题的有( )
A.①② | B.②④ | C.①③ | D.②③④ |
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