1 . 给出下列四个命题:
(1)若
为假命题,则
、
均为假命题;
(2)命题“
”为真命题的一个充分不必要条件可以是
;
(3)已知函数
则
;
(4)若函数
的定义域为R,则实数
的取值范围是
.
其中真命题的个数是( )
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f675824e539f50cec53120959d32e554.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
(2)命题“
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6944539e22a089a80168e2878c9ecc52.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10ede78fd7ac619ea597856254bb5d75.png)
(3)已知函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/589883a5d97f0f7ee75dd0c97e9406bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/289688ca788f9edb554836fd083313f2.png)
(4)若函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6810e2bb8de3e83fd73a4f5690de07b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/389d79319d0694c3d75bbaf19d0a8581.png)
其中真命题的个数是( )
A.0 | B.1 | C.2 | D.3 |
您最近一年使用:0次
A.0 | B.1 | C.2 | D.3 |