如图所示,四边形
为直角梯形,且
,
,
,
,
.
为等边三角形,平面
平面
.
上是否存在一点
,使得
平面
,若存在,请说明
点的位置;若不存在,请说明理由;
(2)空间中有一动点
,满足
,且
.求点
的轨迹长度.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fa7bbd7831e9ff4f8cffc8889d34f05.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97f98f2f71e43a9ec16c40225b747f08.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3df3f49493b1f7317cbe2e95e79338a3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef0402dd5ae3db10281f9f1e11738bcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18120a244d3a1f9c1688bf53eb2ad775.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f392cf697f88fc22678b5d02cbffb94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e742966e3711cfa53dce04022acf4bcc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed5f0cfc1049f84a04c81bd213afb8d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fa7bbd7831e9ff4f8cffc8889d34f05.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84b859ca54ab085edf70c1179a7d103a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c09afc70f448545336304333d5b5658b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
(2)空间中有一动点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b7a460e0a6d2d564e588982a6f55ae4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bcf7cdb0007d84cf53e4f2d0cbf28148.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
更新时间:2024-06-14 22:53:52
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
解题方法
【推荐1】如图,四棱锥
中,底面
为正方形,
,
平面
,
为棱
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/2/5522147d-4293-4ceb-9ce5-8426fc43dabb.png?resizew=247)
(1)求证:
平面
;
(2)求证:平面
平面
;
(3)求二面角
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/62974d34de3a12418d6b700420afd1b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/218054144a13435580cd132b9459546c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/2/5522147d-4293-4ceb-9ce5-8426fc43dabb.png?resizew=247)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30067b7b236d17af8a462f96a58d11bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca48c18021e7be4bbb3e95576e1c1b5f.png)
(2)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(3)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5617a404c5a3356753136e5a6b6d51e5.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
【推荐2】在长方体
中,底面
是边长为2的正方形,
是
的中点,
是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/20/1b66c8b1-dbe7-40da-a95f-78e02b976ca4.png?resizew=149)
(1)求证:
平面
;
(2)若
,求二面角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.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/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/20/1b66c8b1-dbe7-40da-a95f-78e02b976ca4.png?resizew=149)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57f9d682e5d3cc8573574d8d11636758.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a40d8806b86572352ed08aa2b7f89f7.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f7e8dd831f4edc711c0f7d5f078f625.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59a45cf29c2dd5e427b26e071c8bd542.png)
您最近一年使用:0次
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,底面
为矩形,
,点
为线段
上的点,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/16/f4898755-15f6-4a0c-8134-3d7141d4be39.png?resizew=184)
(1)证明:
平面
;
(2)若
,且在线段
上存在一点
,使得![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
平面
.请确定点
的位置.并证明你的结论.
![](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/cb521988dc5f4b42e81e83470eaa134e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4999d4fbcbe15f78c29d518f25d317c2.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/16/f4898755-15f6-4a0c-8134-3d7141d4be39.png?resizew=184)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3727c456a25e9dc4f59ce9da4d70ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb31ef428bd9de9bc875b343feded3c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a29292b2a3a66375202bca1fb986ecb6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐2】如图,三棱柱ABC-A1B1C1中,平面ABB1A1⊥底面ABC,
,∠A1AB=120°,D、E分别是BC、A1C1的中点.
![](https://img.xkw.com/dksih/QBM/2015/5/4/1572094305280000/1572094311366656/STEM/d41918ff19c94d048f84e8f2bf385a94.png)
(Ⅰ)试在棱AB上找一点F,使DE∥平面A1CF;
(Ⅱ)在(Ⅰ)的条件下,求多面体BCF-A1B1C1的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c94627d87f3bed1e6640bb9309a768c.png)
![](https://img.xkw.com/dksih/QBM/2015/5/4/1572094305280000/1572094311366656/STEM/d41918ff19c94d048f84e8f2bf385a94.png)
(Ⅰ)试在棱AB上找一点F,使DE∥平面A1CF;
(Ⅱ)在(Ⅰ)的条件下,求多面体BCF-A1B1C1的体积.
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1】阅读下面题目及其解答过程.
以上题目的解答过程中,设置了①~⑤五个空格,如下的表格中为每个空格给出了两个选项,其中只有一个符合推理,请选出符合推理的选项,并填写在答题卡的指定位置(只需填写“A”或“B”).
如图,已知正方体![]() ![]() (Ⅰ)求证: ![]() (Ⅱ)求证:直线 ![]() ![]() 解:(Ⅰ)如图,连接 ![]() 因为 ![]() 所以 ![]() ![]() 所以①___________. 因为四边形 ![]() 所以②__________. 因为 ![]() 所以③____________. 所以 ![]() (Ⅱ)如图,设 ![]() ![]() ![]() 假设 ![]() ![]() 因为 ![]() ![]() ![]() ![]() 所以⑤__________. 又 ![]() 这样过点 ![]() ![]() ![]() 所以直线 ![]() ![]() |
空格序号 | 选项 |
① | A.![]() ![]() |
② | A.![]() ![]() |
③ | A.![]() ![]() ![]() ![]() |
④ | A.![]() ![]() |
⑤ | A.![]() ![]() ![]() |
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐2】如图,三棱锥
中,
平面
,
,
,点E,F分别是
,
的中点.
![](https://img.xkw.com/dksih/QBM/2021/4/21/2704842266460160/2704882323218432/STEM/687e7f2e87a9431d9a1c7299a96643e9.png?resizew=169)
(1)求证:
平面
;
(2)求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97f30533da2e1d2a958dc906c37eba9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ff7bd82b90112fa0f8383b069564b6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed10df4140819d5451773a45de66201b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://img.xkw.com/dksih/QBM/2021/4/21/2704842266460160/2704882323218432/STEM/687e7f2e87a9431d9a1c7299a96643e9.png?resizew=169)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e56fdf217165748fafe938b64fa08179.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6261790c66cc71ee3898afabad0c09f4.png)
您最近一年使用:0次