如图,在边长为2菱形ABCD中,
,且对角线AC与BD交点为O.沿BD将
折起,使点A到达点
的位置.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/22/f05f8065-1768-43f1-bf51-dfabfb8375e6.png?resizew=162)
(1)若
,求证:
平面ABCD;
(2)若
,求三棱锥
体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00ec435aa1401dbce7863b531bf2f3e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/22/f05f8065-1768-43f1-bf51-dfabfb8375e6.png?resizew=162)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/685534ba47e83433200ce29660875118.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c380c326070941e76ffbc2fc08ecf45.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00de3b5f3920068743971c8f05638863.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db4c18aba9681a8475968248764d4c3a.png)
更新时间:2020-03-03 20:31:56
|
相似题推荐
解答题-问答题
|
适中
(0.65)
解题方法
【推荐1】如图所示,在三棱锥P﹣ABC中,△PAB,△ABC均是等边三角形,PA⊥AC.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/21/fcb682a5-33ec-4449-9f25-e163aaf8b83a.png?resizew=116)
(1)证明:AB⊥PC;
(2)若PC=2,求三棱锥P﹣ABC的体积.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/21/fcb682a5-33ec-4449-9f25-e163aaf8b83a.png?resizew=116)
(1)证明:AB⊥PC;
(2)若PC=2,求三棱锥P﹣ABC的体积.
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解答题-问答题
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适中
(0.65)
解题方法
【推荐2】如图所示,四边形ABCD为矩形,
,
,平面
平面ABE,点F为CE中点.
![](https://img.xkw.com/dksih/QBM/2022/1/24/2901618141175808/2903058741755904/STEM/ee471dc2bbad466698e2e25dc20cd220.png?resizew=155)
(1)证明:
;
(2)求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c9a88fef08e97af66c9a248632eda6b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1bbf6796681347c82b07c4dd30800f1a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cf9a6db3571fa57bfa2d5e4d44c51b3.png)
![](https://img.xkw.com/dksih/QBM/2022/1/24/2901618141175808/2903058741755904/STEM/ee471dc2bbad466698e2e25dc20cd220.png?resizew=155)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f2a245381e615882ee5feb7793a1df6.png)
(2)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/820a55066be63da11d346175942b09aa.png)
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解答题-问答题
|
适中
(0.65)
【推荐1】如图,三棱柱
中,侧面
为菱形,
.
![](https://img.xkw.com/dksih/QBM/2018/2/25/1889982062616576/1892707424845824/STEM/24006250b0714b7b9aa80fdc8700dfd0.png?resizew=265)
(1)证明:
;
(2)若
,求二面角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58cc6184b191e6da43911e701121517e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00ee347187fbbfe9e8a6faf286795d79.png)
![](https://img.xkw.com/dksih/QBM/2018/2/25/1889982062616576/1892707424845824/STEM/24006250b0714b7b9aa80fdc8700dfd0.png?resizew=265)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7870cee007535b979d35bc7feab75616.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d579d07ced4cc2c657ecfa0db385ae1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51634de857372030f517736f256808f8.png)
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解答题-证明题
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适中
(0.65)
名校
解题方法
【推荐2】如图,在棱长为
的正方体
中,点
是
中点.
![](https://img.xkw.com/dksih/QBM/2020/9/12/2548387278536704/2550966375800832/STEM/221ee527ae3349be8a41989f4dac1656.png?resizew=245)
(1)求证:平面
平面
;
(2)求二面角
的正切值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://img.xkw.com/dksih/QBM/2020/9/12/2548387278536704/2550966375800832/STEM/221ee527ae3349be8a41989f4dac1656.png?resizew=245)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9578aee1ffa7a74c04debf1679b068d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77d6935297fc11127a0927a046a2e76a.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd190b5a26dfb45a06c1d6ee86dd82d9.png)
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