如图,在四棱锥
中,平面
平面
,
∥平面
,
,
,
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/30/3a2717c1-a36d-4fdc-a077-07193b8c68d8.png?resizew=178)
求证:(1)
∥平面
;
(2)平面
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4aa9084b8fe0fe05c4388d1f835587b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45acdbac251ca6b76a166c1242e71df9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84d83824f8e902ce1e553de262e28924.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/30/3a2717c1-a36d-4fdc-a077-07193b8c68d8.png?resizew=178)
求证:(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
(2)平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/78a3fd5284e160896f07ce367645fd04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
更新时间:2019-09-07 23:35:53
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
【推荐1】在如图所示的空间几何体中,平面
平面ABC,
是边长为2的等边三角形,BE=2,BE和平面ABC所成的角为60°,且点E在平面ABC上的射影落在
的平分线上.
![](https://img.xkw.com/dksih/QBM/2015/4/13/1572068851548160/1572068857208832/STEM/6ba9fe8a8dd246c79832ab152e0ebe9b.png?resizew=233)
(1)求证:DE//平面ABC;
(2)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17580410bf63dba4fe164265afaac4cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35f5b99642cf3284c32c70e2c1465d5c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d39b8d91afc34e4a9b0fdbb6bafb9087.png)
![](https://img.xkw.com/dksih/QBM/2015/4/13/1572068851548160/1572068857208832/STEM/6ba9fe8a8dd246c79832ab152e0ebe9b.png?resizew=233)
(1)求证:DE//平面ABC;
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/325fbf7c39864c58789bc8ebe853dbe9.png)
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解答题-问答题
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适中
(0.65)
名校
【推荐2】如图,直四棱柱
的底面是菱形,
,
,
,
分别是
,
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/10/d9ff053a-75a2-409e-9cbc-2771c1876d68.png?resizew=169)
(1)证明:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0aa142bb96af98b846997e681609739f.png)
(2)证明:
平面
;
(3)求面
与面
夹角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d19b6bccaa2a17808d1533aa136c17e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.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/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3726450efcb4a70c6ffcb611ab58e9e7.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/10/d9ff053a-75a2-409e-9cbc-2771c1876d68.png?resizew=169)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0aa142bb96af98b846997e681609739f.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edcf19a7f0dd0cdf59516ae585025110.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb5a463a03c549b0dba6d90e7f16a2af.png)
(3)求面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7053e46617fae4a53075ba29d7eb4185.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5c1584736060efe3c605285ba6dd25b.png)
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解答题-证明题
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适中
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名校
解题方法
【推荐1】如图,四棱锥
的底面是矩形,
底面
,
,
分别为
,
的中点,
与
交于点
,
,
,
为
上一点,
.
(1)证明:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3fafdd7404f20232cc39c990b19d8ed4.png)
(2)求证:平面
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.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/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e69d2b798744645af88a4fa411344a83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c406e7d1e7977dd5b30ef81cfdc8e8d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/267ace52b64e1e7dfc5211e033255b7d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf3834d7ec7531f3c3c0ce9b286f7a49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a26427f7523d2a63e760b83340d3dcb.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/20/296670b0-6fca-467b-b627-3309bde1f67e.png?resizew=179)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3fafdd7404f20232cc39c990b19d8ed4.png)
(2)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d077f6da8b2c00b152d4679aa2ed7f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ee7e6c0b8caf5c276776d3e968e851f.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
解题方法
【推荐2】如图:在直角三角形
中,已知
,
,
,
为
的中点,
为
的中点,
的延长线交
于
,将
沿
折起,二面角
的大小记为
.
![](https://img.xkw.com/dksih/QBM/2022/4/22/2963682892808192/2964977466089472/STEM/7b068b2d-3d7f-4c57-8480-1a2710c7b87f.png?resizew=179)
(1)求证:平面
平面
;
(2)当
时,求点
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d42e97eee705d164e6ac6de9ecd6d1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c3cbaef6648895a366bf56f415b70ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8fb7e47e7affbcc9949d6e82ed3481c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fc66a96c1297e7068e987e0e70723e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://img.xkw.com/dksih/QBM/2022/4/22/2963682892808192/2964977466089472/STEM/7b068b2d-3d7f-4c57-8480-1a2710c7b87f.png?resizew=179)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be202354cc5457916b91330b47b729e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5128f894d192816321cabcecdff6c170.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8fd148d264bc9043396f777523e907aa.png)
您最近一年使用:0次