如图,在四棱锥
中,
底面
,
,
,
,
,
,
是
的中点.
![](https://img.xkw.com/dksih/QBM/2021/1/24/2643070521409536/2644342555025408/STEM/5fa15c8580e14acfae967cdc41cec12e.png?resizew=192)
(1)求证:
平面
;
(2)求二面角
的余弦值.
![](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/ae1e04eeb4de72e5750dae77bcb6f88a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b80ee363635d73f601654339028daec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ced06b71073e1bb777f326f06016ce17.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25eb757d05fbff80d50c3bb8dbcb8657.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://img.xkw.com/dksih/QBM/2021/1/24/2643070521409536/2644342555025408/STEM/5fa15c8580e14acfae967cdc41cec12e.png?resizew=192)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e0684e0b09b04661c602437982c0397.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/698335f4880c7a298f4898c83b6562bf.png)
更新时间:2021-01-26 11:11:36
|
相似题推荐
解答题-问答题
|
适中
(0.65)
名校
解题方法
【推荐1】圆柱
如图所示,
为下底面圆的直径,
为上底面圆的直径,
底面
,
,
,
.
![](https://img.xkw.com/dksih/QBM/2022/5/25/2986891897692160/2987724381298688/STEM/5a8b1c56-2246-4566-89d0-40b77e3baf1d.png?resizew=155)
(1)证明:
面
.
(2)求圆柱
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abd13974aebe38eb2a1d744a01ea5aa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a5928c98b341b16d4b5a5b931d2929d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2d212c1709b8e72a055cf1b5381ef64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7de966c316db1013defc56372fcf814e.png)
![](https://img.xkw.com/dksih/QBM/2022/5/25/2986891897692160/2987724381298688/STEM/5a8b1c56-2246-4566-89d0-40b77e3baf1d.png?resizew=155)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/574a6cff0aca240f071ed933c28e32f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46e2da608b66c9aee03e2503388ba4fd.png)
(2)求圆柱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abd13974aebe38eb2a1d744a01ea5aa5.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐2】如图,菱形
与正三角形
所在平面互相垂直,
,
,
分别是线段
,
的中点.
![](https://img.xkw.com/dksih/QBM/2021/6/29/2753485709402112/2760028190441472/STEM/ff147179b6ad48a59ea4062bae0f5cab.png?resizew=221)
(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/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/134ef0b1a2669a09f05bd4dc2496f706.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00ec435aa1401dbce7863b531bf2f3e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cae70b8a9d2d2e96dea62c00ced04b9.png)
![](https://img.xkw.com/dksih/QBM/2021/6/29/2753485709402112/2760028190441472/STEM/ff147179b6ad48a59ea4062bae0f5cab.png?resizew=221)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e60db93cd34a54c98da9ff9782656c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/134ef0b1a2669a09f05bd4dc2496f706.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c96bc9a285172c48e4726ee6492670ef.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐1】如图,圆
的半径为
,
、
是圆
的两条互相垂直的直径,
为
的中点,
.将此图形沿着
折起,在翻折过程中,点
对应的点为
.
![](https://img.xkw.com/dksih/QBM/2021/3/7/2672963776921600/2672992952459264/STEM/467517dc-036d-4ce6-995a-3287e910a07f.png?resizew=518)
(1)证明:
;
(2)当
时,求二面角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8860d9787671b53b1ab68b3d526f5ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.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/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0bd8a97f37156cec6592795da3941f87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://img.xkw.com/dksih/QBM/2021/3/7/2672963776921600/2672992952459264/STEM/467517dc-036d-4ce6-995a-3287e910a07f.png?resizew=518)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76d2c127e203a0cf07921d8386902c6b.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a90d6f16f1bfa7a67ba5987f249ce6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/849e9b7d8884ce1dc513e882bc98fd61.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
【推荐2】如图,在三棱锥
中,
平面
,
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e91ac38719ac70e0597a72e7f0deceac.png)
.
(1)求点
到平面
的距离;
(2)设点
为线段
的中点,求二面角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e0595498034037b58538f8056dbc6f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e91ac38719ac70e0597a72e7f0deceac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd516e4b396722941982a389ee6e524c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/26/a1dcce74-de00-4502-b86e-200dd621794c.png?resizew=109)
(1)求点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(2)设点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da0f73cf7ab0c2a8a0099cb2873c81f4.png)
您最近一年使用:0次