14-15高二上·云南玉溪·期末
1 . 下列说法:
① “
,使
>3”的否定是“
,使
3”;
② 函数
的最小正周期是
;
③“在
中,若
,则
”的逆命题是真命题;
④“
”是“直线
和直线
垂直”的充要条件;
其中正确的说法是_____________ (只填序号).
① “
![](https://img.xkw.com/dksih/QBM/2013/10/7/1571364675035136/1571364680130560/STEM/aa455b8f3e534dedb2b76dc9481bf0ab.png?resizew=52)
![](https://img.xkw.com/dksih/QBM/2013/10/7/1571364675035136/1571364680130560/STEM/5aa1057424a34a0b93c031db0b51750a.png?resizew=18)
![](https://img.xkw.com/dksih/QBM/2013/10/7/1571364675035136/1571364680130560/STEM/2c79406404a2454e9e5073ca936bbd2e.png?resizew=55)
![](https://img.xkw.com/dksih/QBM/2013/10/7/1571364675035136/1571364680130560/STEM/2e2c194df17043f48787f677e1c8da15.png?resizew=32)
② 函数
![](https://img.xkw.com/dksih/QBM/2013/10/7/1571364675035136/1571364680130560/STEM/2039444057d74ed696ae9e24c8532738.png?resizew=96)
![](https://img.xkw.com/dksih/QBM/2013/10/7/1571364675035136/1571364680130560/STEM/28fdb2b485de42a887aa52dcc24bb45e.png?resizew=14)
③“在
![](https://img.xkw.com/dksih/QBM/2013/10/7/1571364675035136/1571364680130560/STEM/ff525fb66c0a43ab94b032fc658f0f48.png?resizew=45)
![](https://img.xkw.com/dksih/QBM/2013/10/7/1571364675035136/1571364680130560/STEM/610e9bac7037486daca72123cba67c14.png?resizew=85)
![](https://img.xkw.com/dksih/QBM/2013/10/7/1571364675035136/1571364680130560/STEM/0097f3f91a89435190cc92933ce1d190.png?resizew=44)
④“
![](https://img.xkw.com/dksih/QBM/2013/10/7/1571364675035136/1571364680130560/STEM/0bfb557c86f64246a45d220cde785fb1.png?resizew=49)
![](https://img.xkw.com/dksih/QBM/2013/10/7/1571364675035136/1571364680130560/STEM/92e3889d300046ee947d4e71cff4bfe8.png?resizew=145)
![](https://img.xkw.com/dksih/QBM/2013/10/7/1571364675035136/1571364680130560/STEM/c8a7cc9367a9463b995195fd007cb533.png?resizew=103)
其中正确的说法是
您最近一年使用:0次
13-14高三上·广东中山·阶段练习
2 . 下列命题中所有真命题的序号是________________ .
①“
”是“
”的充分条件;
②“
”是“
”的必要条件;
③“
”是“
”的充要条件.
①“
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/432d77fe5ad3032d59a237dd94c8a638.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26f7c54faca6eac8af5309942062058d.png)
②“
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/850f6874ea501c6021573701b0294dcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26f7c54faca6eac8af5309942062058d.png)
③“
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/432d77fe5ad3032d59a237dd94c8a638.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0eef30a1357d8d8b6a2de0cd4e960e9.png)
您最近一年使用:0次
11-12高二上·江西抚州·期末
3 . 有下列五个命题:
① 在△
中,
;则命题
是命题
的充要条件;
②
数列
是等差数列,
数列
是单调数列;命题
是命题
的充要条件;
③
△
是锐角三角形,
;则命题
是命题
的充要条件;
④
或
是
成立的必要不充分条件;
⑤
是方程
至少有一个负数根的充分不必要条件.
其中正确的命题序号是____________ .
① 在△
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5935e45f01eaaa941886e48e54e0f990.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51441c8788ff11be766766227793246d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce20ef9c08e82df8c7f45bac6dd31d36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
③
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51441c8788ff11be766766227793246d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2a970321a0506d17b42d937f889da69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
④
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4396ab83803cb86dceb4f0dd72f05111.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07a6f1cf55803d3ef4c5b32e22a337f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a2efb36b16621c0971f975a142c2487.png)
⑤
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e10e1c43b86a8cd4360ca9b57232164.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9080124b199b1e89dc16d0e12af028dd.png)
其中正确的命题序号是
您最近一年使用:0次