如图,在多面体
中,四边形
、四边形
均为菱形,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/17/7c14cd4b-8b07-42dd-a0c9-91357a7ced5b.png?resizew=170)
(1)求证:平面
平面
;
(2)若
,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9165d9bfbb0f0d19eb482c2a4c1b29b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bbc56d42b003cbcb1fbe5c50e55b26b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94fb38612cad92abaf3fb520bfdf93af.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/17/7c14cd4b-8b07-42dd-a0c9-91357a7ced5b.png?resizew=170)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15f3e3f310f6ec3f3a26498e7ee17a00.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bbc56d42b003cbcb1fbe5c50e55b26b.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba11242dcc61d3c7c3555b598b5fdc89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd25fba2c711e1efbbb2d4a0d4b72f3d.png)
2020·全国·模拟预测 查看更多[4]
(已下线)2021届全国著名重点中学新高考冲刺数学试题(4)陕西省榆林市第十中学2020-2021学年高三上学期第五次模拟考试理科数学试题安徽省淮南一中2020-2021学年高二下学期第二次段考理科数学试题安徽省淮南市淮南第一中学2020-2021学年高二下学期期中数学试题(理)
更新时间:2020-11-25 12:50:27
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
【推荐1】已知在图1所示的梯形
中,
,
于点
,且
.将梯形
沿
对折,使平面
平面
,如图2所示,连接
,取
的中点
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/9/e10d6ad6-6f09-40f9-9c0f-bb3b83868ef8.png?resizew=366)
(1)求证:平面
平面
;
(2)在线段
上是否存在点
,使得直线
平面
?若存在,试确定点
的位置,并给予证明;若不存在,请说明理由;
(3)设
,求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b9d54cbbf601f4583659771eb534997.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66418ef39d3081d89411a4907d8599f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff24d05b5b9502c2be337f9be84fe4ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ceae9396dc0551b68ac65b5c4648278.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b9d54cbbf601f4583659771eb534997.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/306b9504b52df5ad6697fa87200e8a44.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/9/e10d6ad6-6f09-40f9-9c0f-bb3b83868ef8.png?resizew=366)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37f39524e24db3f7c9e2f49f35b5e660.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
(2)在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edcf19a7f0dd0cdf59516ae585025110.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fa7bbd7831e9ff4f8cffc8889d34f05.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
(3)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e781a2489271bfd1597cba1bb6f5887.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf910aabe023d18b62268579b6033b18.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
【推荐2】正方体
棱长为2,
,
分别为
和
的中点.
平面
;
(2)求直线
与平面
所成角的正切值.
![](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/f66fb71b75b63594ebeeeebd1963eed5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94270844f197d524bf1da4f1385befd2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐1】如图,四边形
是边长为2的菱形,
,
,
分别为
,
的中点,将
和
沿着
和
折起,使得平面
和平面
均垂直于平面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/19/fb53451b-c945-45da-b292-e32a594b45dd.png?resizew=340)
(1)求证:
平面
;
(2)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43a6f36741b86f464be362b12bac13d2.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/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d4ce3f962c91f0d3c7b998b5fbb37b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274cf35acb4a1748d15c39d15a9bea7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9a32bd7a1b78b5a0ec562c4025aea8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/603c7e98deecdba0cf3773757a9b8304.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2330c01a4d2b5b20f106e3e48834d5c0.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/19/fb53451b-c945-45da-b292-e32a594b45dd.png?resizew=340)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8197bf06d017950c85c3ba6a291c095e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2330c01a4d2b5b20f106e3e48834d5c0.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c909cd1b6f3fa1ec39eb245e8f5c11c.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
【推荐2】如图,在三棱柱
中,
,
.
(1)证明:
;
(2)若
,
,
,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3570a95f68349fcd9417fcda62e78e7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb36baa03b28d2ddb4bafa0cd094d9f8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/22/da5a4dfe-ad56-4de0-9008-b35af5a88915.png?resizew=159)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/943b0dc0ce6e62cb6985d15e5c8baa5b.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4639a9dc0bc99101cbde59fef04b4a2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24a677b42f8b427b21924a559b90141d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0aedf65d7d930fdb972d4802c0dea8b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45cbb74984939d59964559c3560ef7ba.png)
您最近一年使用:0次