真题
1 . 如图,P是边长为1的正六边形
所在平面外一点,
,P在平面
内的射影为
的中点
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/16/6b4dff50-1160-481b-8fdf-27d98751b6bb.png?resizew=151)
(1)证明:
;
(2)求面
与面
所成二面角的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9165d9bfbb0f0d19eb482c2a4c1b29b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcc532cfe64300cb3da9e04a307c957a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274cf35acb4a1748d15c39d15a9bea7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/16/6b4dff50-1160-481b-8fdf-27d98751b6bb.png?resizew=151)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fdb0bc180828ca206181c92c6bcb11e.png)
(2)求面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/745e0525a41fe2e2a7739c75a942290b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5082fa0f36a008dc2838146ea2bf2e1b.png)
您最近一年使用:0次
2022-11-09更新
|
298次组卷
|
2卷引用:2006年普通高等学校招生考试数学(理)试题(安徽卷)
真题
名校
2 . 如图,三棱锥P-ABC中,PA
平面ABC,
.
![](https://img.xkw.com/dksih/QBM/2015/6/24/1572138197737472/1572138203619328/STEM/682b9097-e6d7-4eff-93d5-03933b5491bc.png?resizew=235)
(Ⅰ)求三棱锥P-ABC的体积;
(Ⅱ)证明:在线段PC上存在点M,使得AC
BM,并求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1633988fd62a652de726ee92a917b52d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fb1059f997f4fc86ac37b46bf82120f.png)
![](https://img.xkw.com/dksih/QBM/2015/6/24/1572138197737472/1572138203619328/STEM/682b9097-e6d7-4eff-93d5-03933b5491bc.png?resizew=235)
(Ⅰ)求三棱锥P-ABC的体积;
(Ⅱ)证明:在线段PC上存在点M,使得AC
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1633988fd62a652de726ee92a917b52d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d4838797cff70efabc1e8c1c005e3d6.png)
您最近一年使用:0次
2016-12-03更新
|
2738次组卷
|
10卷引用:2015年全国普通高等学校招生统一考试文科数学(安徽卷)
真题
3 . 平面图形
如图所示,其中
是矩形,
,
,
.现将该平面图形分别沿
和
折叠,使
与
所在平面都与平面
垂直,再分别连接
,得到如图2所示的空间图形,对此空间图形解答下列问题.
.
(1)证明:
;
(2)求
的长;
(3)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3a10276e6c0573116ac78389e768f82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58cc6184b191e6da43911e701121517e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f49563f4b42511cbdd162af849d0c8b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98e486a1aad96167ff62f6fb5136e0bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1b420471f24d3117d0fcc778744f122.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4310db23fc79936c7182361e652bab1a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58cc6184b191e6da43911e701121517e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbcbac9d84e46d80ef138f80b2e3f036.png)
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/21/7a37d374-4872-4414-8ef7-272f945abaf2.png?resizew=223)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc0a886f1192d450ced9fd875e78425e.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
(3)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/524931a902bacd35904905b0a12a947c.png)
您最近一年使用:0次
真题
解题方法
4 . 如图,P是边长为1的正六边形ABCDEF所在平面外一点,
,P在平面ABC内的射影为BF的中点O.
(Ⅰ)证明
⊥
;
(Ⅱ)求面
与面
所成二面角的大小的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcc532cfe64300cb3da9e04a307c957a.png)
(Ⅰ)证明
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274cf35acb4a1748d15c39d15a9bea7b.png)
(Ⅱ)求面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/745e0525a41fe2e2a7739c75a942290b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5082fa0f36a008dc2838146ea2bf2e1b.png)
![](https://img.xkw.com/dksih/QBM/2010/5/5/1569715244613632/1569715250135040/STEM/064601f8-2644-480e-8800-d3e4316c74b6.png?resizew=205)
您最近一年使用:0次