如图,在三棱柱ABC-A1B1C1中,
,
,
面
,
是线段
上的动点,
是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/25/08f37b67-158a-4e6c-9141-41c33672611d.png?resizew=128)
(1)证明:
;
(2)若
且直线
与
所成的角是
,求出
的长,并求三棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/585045d5efe79912edc19823dfa80d82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.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/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/25/08f37b67-158a-4e6c-9141-41c33672611d.png?resizew=128)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b090058790a8cfcdda6c697d5e9c99e.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a4cae354e7c18c7c8b1bae7d53bd06b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e516121599c9fcc528121c00afcf52fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be6a6301878fed2a01413020b27310a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/04c39d0d1cbb21e6812acfd0de2aaa87.png)
更新时间:2020-01-14 17:58:03
|
相似题推荐
解答题-证明题
|
适中
(0.65)
解题方法
【推荐1】如图,已知在四棱锥
中,底面
为矩形,
平面
.
与
的夹角为
,求
的长;
(2)若
,四棱锥
的体积为
,求证:平面
⊥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/8d0d4d498b88fedce31c6040ccdb2c31.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cdba1337ec85fa9722cb4b320a82ae6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/260200d547998bcac50a4a491382e7f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a459372aa54090fcce9430a3cfa182f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35361e76a7c85d1886728c8d0200b234.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f571a1aac46c6d0cf440c0ec2846bf9.png)
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解答题-证明题
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名校
解题方法
【推荐2】如图,以矩形
的
边为直径作半圆
,点
为半圆上一点,满足
,
.将半圆沿
折起,使得半圆面和平面
垂直.
(1)求证:平面
平面
.
(2)若
是半圆弧
上的一点(不包含
两个端点),且异面直线
与
所成角的余弦值为
.是否存在一点
,使得二面角
的余弦值为
?若存在,求出线段
的长度,若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c242819b6e409e1eab675f8e6fea699e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa7aeb2a8d1437eeb4482c3b6ad9f315.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d28c625d7ac6878957facc8274d459c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/500df0e782bb081e608f4bc1d576afcf.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c29a7e8eea08197bf53164a560bee58.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/dee14db57f0c762aad845cf5b4a243c0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a438393ddfc7da1804baf4932442bb35.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5ec70bc9d4f8f5df312e2f09ee3bcb5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
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解答题-问答题
|
适中
(0.65)
【推荐1】如图,在水平放置的四棱锥
中,
平面
,
,
,
.
![](https://img.xkw.com/dksih/QBM/2021/4/28/2709693311049728/2798224034095104/STEM/8d64896f-9f13-4a2b-868b-ea61b5d2bc2b.png?resizew=217)
(1)
为线段
上动点,试确定点
的位置,使
并证明;
(2)求二面角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc655b4d76a5b4d74271082ced237657.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e04a28a7f47d499eaf7451d5a6c3872.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b9d54cbbf601f4583659771eb534997.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8372da7e78999d2016ce485fba43ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf410aab32ba002b2c4e7343e7efd4c4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d81ddfbd5549f312ade47cb7f740059.png)
![](https://img.xkw.com/dksih/QBM/2021/4/28/2709693311049728/2798224034095104/STEM/8d64896f-9f13-4a2b-868b-ea61b5d2bc2b.png?resizew=217)
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dee2d6f5c8afb4081176d398a8f0469.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11c3762eb09409441a1d1d7c0ccbbe60.png)
您最近一年使用:0次
解答题-证明题
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名校
【推荐2】如图所示,在棱长为2的正方体
中,
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/16/9d08040e-42a4-4e3a-9446-a703bdaec31b.png?resizew=167)
(1)求证:
;
(2)求证:
;
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/688ded2b11bec14b5fdec97add4848a2.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/16/9d08040e-42a4-4e3a-9446-a703bdaec31b.png?resizew=167)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/687b84d99861c0efa5c20af61fba78a8.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bbea35579e39f3430d7a0ab3b2a984af.png)
您最近一年使用:0次
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【推荐3】如图,已知梯形
中,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/810ee7bc82b6f452afb3fc18691abc3b.png)
,
,矩形![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd1e2c273d6413383af978b52b1cd64f.png)
平面
,且
,
.
![](https://img.xkw.com/dksih/QBM/2020/12/18/2616956198297600/2618199995023360/STEM/2fb65533-f032-4df8-a143-2f0495caecaa.png)
(1)求证:
;
(2)求二面角
的正切值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/810ee7bc82b6f452afb3fc18691abc3b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1134c8e3440abb6cd385af2c169037fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd1e2c273d6413383af978b52b1cd64f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1633988fd62a652de726ee92a917b52d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3df3f49493b1f7317cbe2e95e79338a3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d815d80ce7e9542e12b84a2f066092f1.png)
![](https://img.xkw.com/dksih/QBM/2020/12/18/2616956198297600/2618199995023360/STEM/2fb65533-f032-4df8-a143-2f0495caecaa.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7bd02e0adeae92ba9526261b1baf797.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19fa7ff056747ebdc342dc2ddf1b4b16.png)
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