如图,在三棱锥
中,
是边长为2的正三角形,
,
,
为
上靠近
的三等分点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/3/b0a8850a-03e0-4942-b331-2390bc331c10.png?resizew=235)
(1)若
,求证:平面
平面
;
(2)当三棱锥
的体积最大时,求点
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fbfcae2cecc98e2d6c16dde6d3ec1c1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3ca0f2b2b40440365fcce22ac32c0ef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04a0681a8b971b80760a26a66defa6cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/3/b0a8850a-03e0-4942-b331-2390bc331c10.png?resizew=235)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3755b2bcf7516eedb26a27ad73657216.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/342d452a7b850cd3a15b23619ad39bd7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b60870baa5e3fbc33a749aa5f0a94be.png)
(2)当三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
更新时间:2022-07-25 13:07:15
|
相似题推荐
解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐1】如图,在四棱锥
中,
ABCD,四边形ABCD是菱形,
,M,N分别为
的中点.
(1)证明:
平面
;
(2)若
,求点N到平面
的距离.
![](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/e39df09be2183c9b5c2f066bb3f5f938.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05740f0c6071846227dc0ec177ad15e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d43ee0103b789698d981f768f0e5b9fd.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/5/4bd2a09e-5857-41b1-b8c9-cb6c0ef3bf1c.png?resizew=164)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edcf19a7f0dd0cdf59516ae585025110.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f83a04565a8ebaa111894b724b0ba266.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.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】如图所示,直角梯形ACDE与等腰直角△ABC所在平面互相垂直,F为BC的中点,
,AE
CD,DC=AC=2AE=2.
(Ⅰ)求证:平面BCD
平面ABC
(Ⅱ)求证:AF
平面BDE;
(Ⅲ)求四面体B-CDE的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edc306485b010bdec4281bc68909c08b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895d6f710d5f67e1d4c7408d50d77281.png)
(Ⅰ)求证:平面BCD
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1633988fd62a652de726ee92a917b52d.png)
(Ⅱ)求证:AF
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895d6f710d5f67e1d4c7408d50d77281.png)
(Ⅲ)求四面体B-CDE的体积.
![](https://img.xkw.com/dksih/QBM/2012/2/22/1570765186605056/1570765192044544/STEM/2b4cba8a5f0748eda64285d7727cbec9.png?resizew=184)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
解题方法
【推荐1】如图,在四棱锥P﹣ABCD中,底面ABCD为梯形,平面PAD⊥平面ABCD,BC∥AD,PA⊥PD,AB⊥AD,∠PDA=60°,E为侧棱PD的中点,且AD=2BC.
(1)求证:CE∥平面PAB;
(2)若点D到平面PAB的距离为2,且AD=2AB,求点A到平面PBD的距离.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/9/21/af144138-a26d-4fe7-8aab-2e0cfcc1de84.png?resizew=170)
(1)求证:CE∥平面PAB;
(2)若点D到平面PAB的距离为2,且AD=2AB,求点A到平面PBD的距离.
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解答题-证明题
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适中
(0.65)
解题方法
【推荐2】四棱锥P-ABCD中,底面ABCD为直角梯形,AB∥CD,∠BAD=90°,CD=2AB=2,PA⊥平面ABCD,PA=AD=
,M为PC中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/29/010307a8-5f32-4ed1-9e02-8fdd4f32f6e9.png?resizew=164)
(1)求证:平面PBC⊥平面BMD;
(2)求点B到平面PCD的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf298f00799cbf34b4db26f5f63af92f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/29/010307a8-5f32-4ed1-9e02-8fdd4f32f6e9.png?resizew=164)
(1)求证:平面PBC⊥平面BMD;
(2)求点B到平面PCD的距离.
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐1】如图,在四面体
中,
是直角三角形,且有
,
为正三角形,且有
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/23/e3283e9b-3852-4c8a-9b76-61451e90b56c.png?resizew=160)
(1)证明:平面
平面
;
(2)延长
到点E,使用得
,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ac451db3443cabb204f96c31fd4a02e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b757f0c42ae5c9a2d6a4b19e5877b27.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/23/e3283e9b-3852-4c8a-9b76-61451e90b56c.png?resizew=160)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17580410bf63dba4fe164265afaac4cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
(2)延长
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd522cb25d036347ce050532f932c904.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b98d08cb05a894f940009f56c74d83c.png)
您最近一年使用:0次
【推荐2】如图,六面体
中,四边形
是正方形,四边形
为直角梯形,
,
,
,
.
平面
;
(2)设三棱锥
的体积为
,六面体
的体积为
,求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ee947130b72cccc577463e7c3d6e46f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a02b1139e07e431b5d4276757b232bad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85098ba8b372b8cf825382d6760c9aca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94975dd7751fbaa083bf8b8149e3cdb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f3de738c5bf1d9b164587c8c1f85849.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a01c00cd74fa21e66d35d260fefa2e96.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9452d486590c872a0d9db0d9967159a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/335187895f612ce811414cfbedf89467.png)
(2)设三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a89fcfc5771191481bc2be0ac322e536.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4764374bd2fb78e59cd0b283637baeb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ee947130b72cccc577463e7c3d6e46f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c63055a5d6916f99d07fede49120753f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f737b04ce09bc7e1ed86dc9b3c85203b.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
【推荐1】如图,在四棱锥
中,底面
为直角梯形,平面
平面
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/28/c3214260-742e-4575-b67b-cbc0bc183c06.png?resizew=188)
(1)证明:
平面
;
(2)已知
,
,
,且直线
与平面
所成角的正弦值为
,求平面
与平面
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/342d452a7b850cd3a15b23619ad39bd7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cdb2dd10731b99c0f4f89ee957f8a239.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2951b9f77413d5f062acb300b09de1f6.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/28/c3214260-742e-4575-b67b-cbc0bc183c06.png?resizew=188)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ced06b71073e1bb777f326f06016ce17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/833cfda415649b832cc136caed392753.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a88c44f558705de3bcefcfc0ece96b8f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/827ccf0c04aa941ba20d5f4c6068b46b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c54d01623f09f23103f03ba1135fc6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1b489c25405ce48699d4f0a62820bed.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,在四棱锥
中,底面
是直角梯形,且
,
,
,已知平面
平面
,
,
分别为
,
的中点.求证:
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/26/1de3c0d8-ba91-4110-92c5-17948f373697.png?resizew=164)
(1)
平面
;
(2)
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34e0a957a55460c72673c0f2ee90dbb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7ee81b6066188abee9d167b6c7f3f71.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/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/26/1de3c0d8-ba91-4110-92c5-17948f373697.png?resizew=164)
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/307807ee10071bafbe922eb18d2517d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/134ef0b1a2669a09f05bd4dc2496f706.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2ffc6952e988d04f22f0fb2f7f0ab7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/134ef0b1a2669a09f05bd4dc2496f706.png)
您最近一年使用:0次