如图,在四棱锥
中,
平面ABCD,底面ABCD是正方形,AC与BD交于点O,E为PB的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/2/2487c566-044e-441d-a5ae-fafe259a4fc3.png?resizew=152)
(1)求证:
平面PDC;
(2)求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/2/2487c566-044e-441d-a5ae-fafe259a4fc3.png?resizew=152)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebca490fc8af91b6b3b5e0a33af2968c.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b757706eee506a078fc25e3f33a70cb.png)
更新时间:2020-01-04 16:30:10
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
【推荐1】已知四边形
为直角梯形,
,
,
为等腰直角三角形,平面
平面
,E为
的中点,
,
.
平面
;
(2)求证:平面
平面
.
(3)求异面直线
与
所成角的余弦值;
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4795ee1f96b430529934e2231b38885d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f571396be1aa4a8914a66f7d7abd6381.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf1f5a0775c66f7e8bcff719c82f04de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5827a006e69fc21a86abe63f86b7e2c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c36a60e9b0fe8fe15d7b5ff8a1602e30.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7175df06e33cad4e6bbc3f2f6b0a2986.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/218054144a13435580cd132b9459546c.png)
(2)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4aa9084b8fe0fe05c4388d1f835587b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f571a1aac46c6d0cf440c0ec2846bf9.png)
(3)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
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解答题-证明题
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适中
(0.65)
名校
【推荐2】如图,在三棱柱
中,
底面
,且
为等边三角形,
,D为
的中点.
![](https://img.xkw.com/dksih/QBM/2021/6/11/2740926850228224/2741197143851008/STEM/3a002a9e-bb70-4612-a420-260d16e12b5b.png?resizew=256)
(1)求证:直线
平面
;
(2)求证:平面
平面
;
(3)求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5845ccc0d735dc14c92a8926d9b1def6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/565517c781e119de8d8e9c9f29e4e2dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://img.xkw.com/dksih/QBM/2021/6/11/2740926850228224/2741197143851008/STEM/3a002a9e-bb70-4612-a420-260d16e12b5b.png?resizew=256)
(1)求证:直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1496afecd92a619fbe5e9b736f06f4e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a935b7d21a103a264b6e96ecf82dbe4a.png)
(2)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f7d9ac3c0e60f1419dc90a37ff731b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d9a8181f7a7fe7f3fac872ce9534f15.png)
(3)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53997d627b71f60a18b770e44bb21515.png)
您最近一年使用:0次
解答题-证明题
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适中
(0.65)
【推荐1】如图,在四棱锥
中,
为正三角形,
,
,
,
,
为线段
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/1/765b840b-e478-4b26-bf64-369edcd22ddc.png?resizew=183)
(1)求证:
平面
;
(2)求证:
平面
;
(3)求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7305de9211785b826823153897b17517.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5b0382c28547d3834ca71f3f0677695.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/381d7665edf20fda970fd3f4d1cadc1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c85aeab3aeaf4367b711da8cde2e8bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/1/765b840b-e478-4b26-bf64-369edcd22ddc.png?resizew=183)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0457394ce4f2dc8d940c565c94dcf557.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bc46688d8723cf2003fc25890265200.png)
(3)求三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8ca90486f5edcf87de3cd818fc9189a.png)
您最近一年使用:0次
解答题-证明题
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适中
(0.65)
【推荐2】如图,在直三棱柱
中,
,
.
平面
;
(2)若
,
分别为棱
,
上的动点,且
.当三棱锥
的体积最大时,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3f35646cb29fafd1e1a214b69e4f22d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12d3d5c6d668afddb0603556c9133996.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e56fdf217165748fafe938b64fa08179.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9b7b7793d29d66dfdd89e7a6564a35c.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3eac6f98ed81727dc5f6699ea5117fff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb4f66c9a5b559123c504b59b9466738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b16a65e7b9d79ba75c14c36998985d94.png)
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解答题-作图题
|
适中
(0.65)
名校
【推荐3】如图,在三棱锥
中,
和
均是边长为6的等边三角形,P是棱
上的点,
,过点P的平面
与直线
垂直,且平面
平面
.过直线l及点C的平面
平面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/3/aa110b0c-8325-43fa-8b00-1be7821a8028.png?resizew=182)
(1)在图中画出l,写出画法(不必说明理由);
(2)求证:
;
(3)若直线
与平面
所成角的大小为
,求平面
与平面
所成的锐二面角的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6a94d59dee2d5a8f0425b64b2083825.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9f63075fdeeb9e765dd696c4ff43ba1.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd4fce8e923062b9779553d6f282895b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb1319a44dc601303876d3dab3372660.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a392d05d3cfcbb438569b1ea9980dc2.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/863dd235346ce076540230e8eb4122f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/138ca330a165c68e865cacd35c18a665.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cec6c3f8d8a0611bf49e269bd288949d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/3/aa110b0c-8325-43fa-8b00-1be7821a8028.png?resizew=182)
(1)在图中画出l,写出画法(不必说明理由);
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23a63f6aa604e3d7fc7ae8c7b587069a.png)
(3)若直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a392d05d3cfcbb438569b1ea9980dc2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1902d864d3f16535e273f7851b92a4fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b5858ee1ce52b251816757257a11c29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
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