名校
解题方法
1 . 已知正方体
,
,
分别为
,
的中点,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/394c5d2f55221975503be8aa18022480.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
A.直线![]() ![]() ![]() |
B.直线![]() ![]() ![]() |
C.直线![]() ![]() ![]() |
D.直线![]() ![]() ![]() |
您最近一年使用:0次
2022-11-11更新
|
593次组卷
|
3卷引用:浙江省金华十校2022-2023学年高三上学期11月月考数学试题
解题方法
2 . 如图,几何体
中,平面
平面ABC,
,
,
.
![](https://img.xkw.com/dksih/QBM/2022/3/23/2942508286009344/2943028567359488/STEM/9f53c1dd67f9498092dea16e6902bc97.png?resizew=245)
(1)证明:
;
(2)若
,
,求直线DA与平面EAB所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9142a8490de14a87eda628ffa7e28982.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bde1e200d1dd5ddc433c876c9d2f688c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed10df4140819d5451773a45de66201b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9332278351ab92e03e984e9279dd06a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a3a6dcaf9f9e9a940b4a16f7ec2fc2d.png)
![](https://img.xkw.com/dksih/QBM/2022/3/23/2942508286009344/2943028567359488/STEM/9f53c1dd67f9498092dea16e6902bc97.png?resizew=245)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fd260fb9d772c122dcb1df52cbe38ab.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c776123acaded2ccf842d180b9f7741a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b547d886c528fa2c63016c217b8fb51.png)
您最近一年使用:0次
名校
3 . 已知三棱锥
中,
,且
,长度为1的线段
的端点
在
上,端点
在侧面
内运动,若
的中点为
,
的重心为
,则
的最小值是_________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81ff2c282e317373b88cb632ad96b195.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f7baa13630f448b194478cb862e620f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b68df477b3ee45ac0f725db00d465a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ced36ad180a287548ea22cbf5ddb746.png)
您最近一年使用:0次
名校
4 . 已知直三棱柱
的侧棱长为6,且底面是边长为2的正三角形,用一平面截此棱柱,与侧棱
,
,
分别交于三点
,
,
,若
为直角三角形,则该直角三角形斜边长的最小值为( ).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed283a253b61df01f2a1cdc0cd8003f3.png)
A.2 | B.4 | C.![]() | D.![]() |
您最近一年使用:0次
2020-06-08更新
|
546次组卷
|
2卷引用:浙江省宁波市镇海中学2018届高三下学期5月模拟考试数学试题
解题方法
5 . 在四棱柱
中,
平面
,底面
是边长为
的正方形,侧棱
的长为
,
为侧棱
上的动点(包括端点),则
![](https://img.xkw.com/dksih/QBM/2015/7/1/1572159116730368/1572159122382848/STEM/adb2ca5c-2d20-4fb3-a528-0b80c8d26a96.png?resizew=140)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5845ccc0d735dc14c92a8926d9b1def6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/632f2bf1cd0435041fa04b01901d1c8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/632f2bf1cd0435041fa04b01901d1c8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://img.xkw.com/dksih/QBM/2015/7/1/1572159116730368/1572159122382848/STEM/adb2ca5c-2d20-4fb3-a528-0b80c8d26a96.png?resizew=140)
A.对任意的![]() ![]() ![]() ![]() |
B.当且仅当![]() ![]() ![]() |
C.当且仅当![]() ![]() ![]() |
D.当且仅当![]() ![]() ![]() |
您最近一年使用:0次