1 . 函数
的定义域为![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a43b2faa4f81f32d94612dce724e772b.png)
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca543ad54da566e2befd9f1fc64ed2ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a43b2faa4f81f32d94612dce724e772b.png)
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2 .
是
的充分不必要条件( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83455d9448b63a6eae1565280d6a6111.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84111bc3ad9247785ee53f306d1250bc.png)
您最近一年使用:0次
3 . 若
是全集
的一个非空子集,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4411598e6ff48451beba0dcf3131e460.png)
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4411598e6ff48451beba0dcf3131e460.png)
您最近一年使用:0次