1 . 命题“
”的否定是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0a52d689ef04f5eba29d788b1d7b22d.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
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2 . 已知命题
:
,
,则
是
![](https://img.xkw.com/dksih/QBM/2016/3/2/1572511151292416/1572511157035008/STEM/545b7fb24fcf49ef964b88317b873b76.png)
![](https://img.xkw.com/dksih/QBM/2016/3/2/1572511151292416/1572511157035008/STEM/7285bc3275e9437db46d14c99798fa53.png)
![](https://img.xkw.com/dksih/QBM/2016/3/2/1572511151292416/1572511157035008/STEM/7b116c3422ab4141bc8e221bd0021b7e.png)
![](https://img.xkw.com/dksih/QBM/2016/3/2/1572511151292416/1572511157035008/STEM/f0e35dafafbe41088022b196d68247aa.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
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3 . 设a,b是实数,命题“
ab>0,都有a>0,b>0”的否定是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1152fe51a6add4d6263e52829cd3c6b.png)
A.![]() |
B.![]() |
C.![]() |
D.![]() |
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4 . 已知命题
:
,
,则
是
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470388686848/1572470394159104/STEM/375febf83b7b4729843e8876509bebba.png)
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470388686848/1572470394159104/STEM/c1b063f0bb1f44b6b429cf9039fd214a.png)
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470388686848/1572470394159104/STEM/8ff35ce74d444f66b1b229b33cf03b57.png)
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572470388686848/1572470394159104/STEM/26ac691e598d4eecaa4747b6790514ae.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
您最近一年使用:0次
5 . 已知命题
;命题
.则下列结论正确的是
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572469086756864/1572469091893248/STEM/968843a6379c4ec79556bad39a6f69f6.png)
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572469086756864/1572469091893248/STEM/47af86cb959a4929a53aaba31e7e1055.png)
A.命题![]() |
B.命题![]() |
C.命题![]() |
D.命题![]() |
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6 . 已知命题
,则
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/911bd39b7299fa65ec9afea7a722d8de.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
您最近一年使用:0次
7 . 命题“
”的否定是
![](https://img.xkw.com/dksih/QBM/2016/1/27/1572467990872064/1572467996614656/STEM/5041e8c6a9634c068c8fa7f44cade3c8.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
您最近一年使用:0次
8 . 给出如下四个命题:
①若“p且q”为假命题,则p、q均为假命题;
②命题“若a>b,则2a>2b﹣1”的否命题为“若a ≤ b,则2a ≤ 2b﹣1”;
③“
x∈R,
”的否定是“
x∈R,
;
④在△ABC中,“A>B”是“sinA>sinB”的充要条件.
其中不正确的命题的个数是
①若“p且q”为假命题,则p、q均为假命题;
②命题“若a>b,则2a>2b﹣1”的否命题为“若a ≤ b,则2a ≤ 2b﹣1”;
③“
![](https://img.xkw.com/dksih/QBM/2016/1/25/1572465695588352/1572465700659200/STEM/866aed6f455b42eba1c41652c320adf7.png)
![](https://img.xkw.com/dksih/QBM/2016/1/25/1572465695588352/1572465700659200/STEM/84d90a1c7a7045b78a3b28ba15ff789a.png)
![](https://img.xkw.com/dksih/QBM/2016/1/25/1572465695588352/1572465700659200/STEM/e7854ed2ba07464eabcd881413fe4a4c.png)
![](https://img.xkw.com/dksih/QBM/2016/1/25/1572465695588352/1572465700659200/STEM/84d90a1c7a7045b78a3b28ba15ff789a.png)
④在△ABC中,“A>B”是“sinA>sinB”的充要条件.
其中不正确的命题的个数是
A.4 | B.3 | C.2 | D.1 |
您最近一年使用:0次
9 . 下列说法正确的是
A.“若![]() ![]() ![]() ![]() |
B.命题“对![]() ![]() ![]() ![]() |
C.![]() ![]() |
D.设p,q是简单命题,若![]() ![]() |
您最近一年使用:0次
10 . 给出下列几个命题:
①命题“若
,则
”的逆否命题为假命题;
②命题
:任意
,都有
,则
:存在
,使得![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a3ecba19917cb95ee17b82f1b4877c4.png)
③命题
:存在
,使得
;命题
:
中,
,则命题“
且
”为真命题
④方程
表示椭圆的充要条件是
.
⑤对空间任意一点
和不共线的三点
,若
,则
四点共面.
其中不正确的个数( )
①命题“若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4120436d6ff0c58109473edc068257c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffb8898d840443e228d34d94056f081e.png)
②命题
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb63478132d4c1fef3c17e591919da83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05611fbe265ef9e3d4a8b1821bcbc1eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ffc1bb9d53a27d484396ad74d6a26e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/070054c0b4182ab7399ed56925844e93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a3ecba19917cb95ee17b82f1b4877c4.png)
③命题
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/070054c0b4182ab7399ed56925844e93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be91c54832cbb241b6a32cb0fab85825.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e60775575f4aa98407260a240a0a75ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ffc1bb9d53a27d484396ad74d6a26e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
④方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdcc6b9277b4ebf983ee846923230c8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d225bb3f1984613ca62d737f6f2a8308.png)
⑤对空间任意一点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e739c2d4754a7421f8b20e3b5bc09074.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90a0889f0f80987c260cce05be4c84b0.png)
其中不正确的个数( )
A.1 | B.2 | C.3 | D.4 |
您最近一年使用:0次