名校
1 . 以下命题错误的序号为( )
①
与
是两条不同的直线,则“
”是“
”的充分不必要条件;
②若“
”是真命题,则“
”一定是假命题;
③荀子曰:不积跬步,无以至千里,不积小流,无以成江海.这说明“积跬步”是“至千里”的充分条件;
④“
”是“
为奇函数”的充要条件.
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79ffcf966fb0d99555aa3862f933ba14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e37c9888b01053e656d567cc2c1dc759.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf0086b054ef120408acac806a1b1318.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02e03566282ef39ad17821036f228174.png)
②若“
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e48ebdd742cb5d310c21a384d599bc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6777065ed14d76944be5cb45d9e2c76.png)
③荀子曰:不积跬步,无以至千里,不积小流,无以成江海.这说明“积跬步”是“至千里”的充分条件;
④“
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/104375baf5cef5eb92cfc7cf13b80193.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
A.①③④ | B.①② | C.③④ | D.①④ |
您最近一年使用:0次
2 . 有以下命题:
①斜率互为负倒数的两直线垂直.
②空间的四个点最多可确定4个平面.
③已知一个平面
,那么对于空间内的任意一条直线
,在平面
内一定存在一条直线
,使得
与
异面.
④已知两条异面直线
,
和两个平面
,
,若
,
,
,
,则
.
其中正确命题的序号为__________ .
①斜率互为负倒数的两直线垂直.
②空间的四个点最多可确定4个平面.
③已知一个平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
④已知两条异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b5858ee1ce52b251816757257a11c29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/539a38ada26356d73024fb8533449c49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/808c6d37467a5c995d71e49408503927.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/209323a7a4d015f7e570ec578c1731f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79018590293277ff2d76452a50ad2dbc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35f747152f006301e03b643afb80195c.png)
其中正确命题的序号为
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3 . 对于下列说法:
①方程
表示的图形是圆;
②对任意实数
,直线
平分圆
;
③若直线
与直线
垂直,则实数
的值为
或
.
④已知圆
的半径为
,
,
为该圆的两条切线,
,
为两切点,那么
的最小值为
.
其中所有正确说法的序号是______ .
①方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd36119f10abe3d734a320580ca530d4.png)
②对任意实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/889e8229d3900a55687af7d5cfa9f283.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b4ee22fbd02d14f7764a81694df5d88.png)
③若直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/132fd1617b4be21e8c520dbaefa413df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c127706d04bcad738d20e24fad70809.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c95b6be4554f03bf496092f1acdfbb89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
④已知圆
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a33e5d0dbdd0f15854f0d7dd8b53058.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc5636bddc636487839d47a0b17eed57.png)
其中所有正确说法的序号是
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2020高三·全国·专题练习
4 . 给出下列说法:
①“若
,则
”的逆命题是假命题;
②“在
中,
是
的充要条件”是真命题;
③“
”是“直线
与直线
互相垂直”的充要条件;
④命题“若
,则
”的否命题为“若
,则
”.
以上说法正确的是________ (填序号).
①“若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58ab5174edcf796e06fc85e28614432f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd62f741b8897536cf616b5774247f6a.png)
②“在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2905b41405398718abd03d8894cf81a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5aa3638653a94a02420f176d860e294e.png)
③“
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b550ee821ee1838384835e81fc34b67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/289ce704ab8d876aa9756cf3ae972a2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af716c494fc62f7d7d60ad4aaf6b7e65.png)
④命题“若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7da6d82d173ad18cc040e94c925b5ab9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0b051e1329de07b78b173b7980ea8ea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/629507dcfdeb6866da428c4f45e2b21d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb6b1fc85c324b4c4defdc8f1012d9ee.png)
以上说法正确的是
您最近一年使用:0次