1 . 给出下列结论:
①设平面α与平面β相交于直线m,直线a在平面α内,直线b在平面β内,且b⊥m,则α⊥β是a⊥b的必要不充分条件.
②在区间[-1,1]上随机取一个数x,则
的值介于0到
之间的概率为![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dac452fbb5ef6dd653e7fbbef639484.png)
③从以正方体的顶点连线所成的直线中任取两条,则所取两条直线为异面直线的概率为![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f053ede9bc7e812d21128cc31a59ad3.png)
④将4个相同的红球和4个相同的蓝球排成一排,从左到右每个球依次对应的序号为1,2,3,…,8,若同色球之间不加区分,则4个红球对应的序号之和小于4个蓝球对应的序号之和的排列方法种数为31.
其中正确结论的序号为___________ .
①设平面α与平面β相交于直线m,直线a在平面α内,直线b在平面β内,且b⊥m,则α⊥β是a⊥b的必要不充分条件.
②在区间[-1,1]上随机取一个数x,则
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a2e51b2fb9409bd4790ca95eb01fa8d1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dac452fbb5ef6dd653e7fbbef639484.png)
③从以正方体的顶点连线所成的直线中任取两条,则所取两条直线为异面直线的概率为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f053ede9bc7e812d21128cc31a59ad3.png)
④将4个相同的红球和4个相同的蓝球排成一排,从左到右每个球依次对应的序号为1,2,3,…,8,若同色球之间不加区分,则4个红球对应的序号之和小于4个蓝球对应的序号之和的排列方法种数为31.
其中正确结论的序号为
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解题方法
2 . 已知正方体
的棱长为1,给出下列四个命题:①对角线
被平面
和平面
三等分;②正方体的内切球,与各条棱相切的球,外接球的表面积之比为
;(3)以正方体的顶点为顶点的四面体的体积都是
;④正方体与以
为球心,1为半径的球的公共部分的体积是
,其中正确命题的序号为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7935fe3125f247b7bea4f065ce9ad985.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b0a582c36d62d83c16425b2f54b4354.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a36ff6bc8e633806c50cc1ab3f30aaa9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e6486784415f3537c9a13556c05d893.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c67d01e61dc0042e67b5e8ec8e727c22.png)
您最近一年使用:0次
2020-03-15更新
|
361次组卷
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3卷引用:上海市七宝中学2018-2019学年高二下学期5月月考数学试题
名校
解题方法
3 . 如图,等腰直角三角形
的斜边
为正四面体
的侧棱,直角边
绕斜边
旋转,则在旋转的过程中,有下列说法:
①四面体
的体积有最大值和最小值;
②存在某个位置,使得
;
③设二面角
的平面角为
,则
.
正确命题的序号是
______
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c09afc70f448545336304333d5b5658b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://img.xkw.com/dksih/QBM/2020/8/2/2519171913875456/2519201541398528/STEM/50937ca6-efb1-4a30-8a50-15654f76583c.png?resizew=304)
①四面体
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42020cfacd62b300cad053981bab9e0b.png)
②存在某个位置,使得
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53c51c25b65a37b676ae3c3b71c29f9b.png)
③设二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d87b527147cb8dbb475bcefc0da2e6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3df1d9dcf1be61e7fa0d74ca9b70a5bc.png)
正确命题的序号是
![](https://img.xkw.com/dksih/QBM/2020/8/2/2519171913875456/2519201541398528/STEM/ef9cda5e20f14506b80f1156c04792cf.png?resizew=13)
![](https://img.xkw.com/dksih/QBM/2020/8/2/2519171913875456/2519201541398528/STEM/59c46a42695d43f681dd46f89bc2aa44.png?resizew=13)
您最近一年使用:0次
2020-08-02更新
|
629次组卷
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3卷引用:安徽省阜阳市太和第一中学2020-2021学年高二(奥赛班)上学期开学考试数学试题
安徽省阜阳市太和第一中学2020-2021学年高二(奥赛班)上学期开学考试数学试题浙江省宁波市效实中学2020届高三下学期6月高考模拟数学试题(已下线)练习5 2021年高考数学二轮小题专练(新高考)
名校
4 . 给出下列两个命题:(1)设
,
,
都是复数.如果
,则
;(2)设
,
,
都是复数,如果
,则
.那么,下述说法正确的是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95563a79e3b68c597ae1e5167516ff88.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd96385362fd2bc879f32ae00e9a6fd3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd96385362fd2bc879f32ae00e9a6fd3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95563a79e3b68c597ae1e5167516ff88.png)
A.命题(1)正确,命题(2)也正确 | B.命题(1)正确,命题(2)错误 |
C.命题(1)错误,命题(2)也错误 | D.命题(1)错误,命题(2)正确 |
您最近一年使用:0次
2018-12-08更新
|
132次组卷
|
2卷引用:上海市复旦大学附属中学2017-2018学年高二下学期期中数学试题