解题方法
1 . 在棱长为1的正方体
中,过面对角线
的平面记为
,以下四个命题:
,使
;
②若平面
与平面
的交线为
,则存在直线
,使
;
③若平面
截正方体所得的截面为三角形,则该截面三角形面积的最大值为
;
④若平面
过点
,点
在线段
上运动,则点
到平面
的距离为
.
其中真命题的序号为____________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83c09eec4e14a861af83d7828797d176.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b239e234d9ae31814af54bf27b7056ba.png)
②若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58cc6184b191e6da43911e701121517e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d0c6947783608bd8f6dc7fdaadad2cb.png)
③若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/821309f088a175c00dc0f4828334503d.png)
④若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97c01fdc7bc471af0b264a04aef0823e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d8772aa893a9c1d40f714cb25701701.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15b78c047642924fe864028c81b1f49d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/827ccf0c04aa941ba20d5f4c6068b46b.png)
其中真命题的序号为
您最近一年使用:0次
2 . 下列四个命题,真命题的个数是________ .
①若
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63af71b9e6f71cd26e6e97541154cd8c.png)
②
的充分不必要条件是![](https://staticzujuan.xkw.com/quesimg/Upload/formula/432d77fe5ad3032d59a237dd94c8a638.png)
③命题“
,
”的否定为“
,
”
①若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24a57996290794e082b21d8f1dfc322a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63af71b9e6f71cd26e6e97541154cd8c.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c22b9d08cf536bbb76bce1b0f135772.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/432d77fe5ad3032d59a237dd94c8a638.png)
③命题“
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/899301a636c6ca1b072877441bcbcc59.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3119d53efb32cd36255815c962be6ff8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c2a51de282f71171aeb8284c4a9cb1e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10f9fdc01e564d4c2e5f7d3c8d0f3db3.png)
您最近一年使用:0次
3 . 下列语句:①
是无限循环小数;②
;③当
时,
;④请把门关上.其中不是命题的是________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf298f00799cbf34b4db26f5f63af92f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1fdf7d28b97fb6fe731703f80e122ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f23d29646155e27b172ecdf263e2d702.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d623cde694da4c9f239f640bb42666fd.png)
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4 . 命题“全等三角形一定相似”的逆否命题是________ .
您最近一年使用:0次
5 . 给出以下四个命题:
①“若
,则x,y互为相反数”的逆命题;
②“全等三角形的面积相等”的否命题;
③“若
,则
有实根”的逆否命题;
④“若
是正整数,则a,b都是正整数”
其中的假命题是_________________ .(写出所有假命题的序号)
①“若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f1a686b80b8f109a929f58c2de7201d.png)
②“全等三角形的面积相等”的否命题;
③“若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ef4d1c906541fb8260cd351707e1b30.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a35c85b538d670f0d97af530abffb76.png)
④“若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18f0281e6bbdbe08beeccb55adf84536.png)
其中的假命题是
您最近一年使用:0次
6 . 已知命题
:双曲线
的渐近线方程为
,命题
:双曲线
的离心率大于2,命题
:方程
有实数解,现有下列四个命题:①
;②
;③
;④
.其中所有真命题的序号为_______
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/348aca26e61218d251581e21c1129a8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/060e229870f126b31e37965bc0c58667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d86c392fcc9b8835f90afb74ed30a72f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11bc05f41215f9894e11d1df0465751a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ccfa090343b3b92bc10ce10b75ff617.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c13472bf0353e16784a22e1f890fba40.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e743a11b4ee929c043c3d921fdc0b3f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73fc0506a5ba900b169b2b794a97d984.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efcc456ba77fb1fed79b06f3ed69cef8.png)
您最近一年使用:0次
2023-03-11更新
|
88次组卷
|
2卷引用:陕西省商洛市2022-2023学年高二上学期期末理科数学试题
名校
7 . 命题
:若
,则
,则其否命题是______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d217c7b12e12e5fb67472452518859ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dfc5f8c0162d3a4be759b4a1d92844a7.png)
您最近一年使用:0次
2023-03-04更新
|
196次组卷
|
2卷引用:陕西省西安交通大学附属中学2019-2020学年高二下学期5月月考理科数学试题
8 . 下列命题中为真命题的是_____________ .(填序号)
①命题“若
,则
”的否命题;
②命题“若
,则
”的逆命题;
③命题“若
,则
”的否命题;
④命题“若
,则
”的逆否命题.
①命题“若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fde64f4d3c38e43fbdee24eadc4b0dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6749db809dd84c2cfe5c47bea121e356.png)
②命题“若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b21208364124b5c477b2ff8df1c2e8f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/552d996f4748a1c0d22149f9ead89f02.png)
③命题“若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b384412acba251d87902ab928902f16.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/828765097c682c0b260c81e5bf6229a6.png)
④命题“若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/432d77fe5ad3032d59a237dd94c8a638.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b34c5832f3fe28f48a924854cb8814ba.png)
您最近一年使用:0次
9 . 下列命题正确的是_________ .(填入序号)
①若命题p为假命题,命题q是真命题,则
为真命题.
②命题“若
与
的夹角为锐角,则
”及它的逆命题均为真命题.
③命题“若
,则
或
”的逆否命题为“若
且
,则
”.
①若命题p为假命题,命题q是真命题,则
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b68befa27a996e2b6543eaf7e36b0091.png)
②命题“若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a2f4b1178f68bd147d1a2a6acd04435.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c94075193c11fe43f2396cff5a485054.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fdbc0945b4e1962e66f6f7e7f6af235d.png)
③命题“若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d905b0b228d2ddb95cf128de5002eedc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb45f673c56a289ea78831c9237e8d20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99c6875d552e9fff3c7d655f3a59b166.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38f0e9c04402a0ffdaa25c3e3c82c7dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31be670d32e753012125c503f2f3be56.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb3e3f3a5ee26b44931b0b1a5b4723e3.png)
您最近一年使用:0次
名校
解题方法
10 . 关于
的方程
,给出下列四个命题:
①不存在实数
,使得方程恰有2个不同的实根;
②存在实数
,使得方程恰有4个不同的实根;
③不存在实数
,使得方程恰有5个不同的实根;
④存在实数
,使得方程恰有8个不同的实根.
其中正确命题的序号是____________ .(写出所有正确命题的序号)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c2f5ce1d4c3ab18efd41533604d8dce.png)
①不存在实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
②存在实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
③不存在实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
④存在实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
其中正确命题的序号是
您最近一年使用:0次