如图,在四棱锥
中,底面
的边长是
的正方形,
,
,
为
上的点,且
平面
.
![](https://img.xkw.com/dksih/QBM/2020/12/21/2618842067263488/2627332542939136/STEM/8792caa1980a4e6d83f567756c629ed2.png?resizew=207)
(1)证明:
平面
;
(2)证明:平面
平面
;
(3)求直线
与平面
所成角的正弦值.
![](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/95bacae35b6e16a0a33c2bdc6bc07df7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62974d34de3a12418d6b700420afd1b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0453cfd7e92bf7746a88280b9e7b580.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a22d6b860f06fe23618b0d3de6768fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f571a1aac46c6d0cf440c0ec2846bf9.png)
![](https://img.xkw.com/dksih/QBM/2020/12/21/2618842067263488/2627332542939136/STEM/8792caa1980a4e6d83f567756c629ed2.png?resizew=207)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1b49f64e0065edad868b25e9fcada3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
(2)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(3)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
更新时间:2021-01-02 10:24:39
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
【推荐1】如图,在四棱锥
中,
为棱
上一点,
,四边形
为矩形,且
平面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/24/7541bda9-7ca6-4eb5-b20c-f27bf284f822.png?resizew=187)
(1)求证:
平面
;
(2)求二面角
的大小.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db5f18c7adab706a76b9762c768c49fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fa7bbd7831e9ff4f8cffc8889d34f05.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb98f75eb139970719cab97a1ba7fdac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87c0bfeadcf17b2a45896071f07a4a5a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/3/24/7541bda9-7ca6-4eb5-b20c-f27bf284f822.png?resizew=187)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ed12dbce4429a93b12a2aaad0da5520.png)
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解答题-问答题
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适中
(0.65)
【推荐2】如图,在四棱锥
中,
底面
,底面
是直角梯形
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/20/d94773bc-6c4d-4108-8c17-1be663e76447.png?resizew=165)
(1)证明:当点
在
上运动时,始终有平面
平面
;
(2)求锐二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5f1897a7e856b42f8cee0f286ad913d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af2ed27ad118ce1479d0168f82b0ce76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89ee6576c35c682bcb0eff43bd958d1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6eea78bf026d76f1cb9cc3dc9349a193.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/20/d94773bc-6c4d-4108-8c17-1be663e76447.png?resizew=165)
(1)证明:当点
![](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/677d1863ff4d8ac1604b18149d4f320f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
(2)求锐二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b33b7213d99a817bff19bcf740a0697c.png)
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解答题-问答题
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适中
(0.65)
【推荐1】在长方体
中,
,
,
是
中点,求:
与平面
所成的角;
(2)
与平面
所成的角.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b37750daa8ba3b3fe3e9e2092f81c848.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f3e58edd1f900ca82bb2a3058293f52.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19ef601ca1f9c4c031adab4ffed297f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19ef601ca1f9c4c031adab4ffed297f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
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适中
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【推荐2】如图,四棱锥P-ABCD中,底面ABCD为矩形,PD垂直于底面ABCD,AD=PD,E分别为AP的中点.
(Ⅰ)求证:DE垂直于平面PAB;
(Ⅱ)设BC =
,AB=2,求直线EB与平面ABD所成的角的大小.
(Ⅰ)求证:DE垂直于平面PAB;
(Ⅱ)设BC =
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf298f00799cbf34b4db26f5f63af92f.png)
![](https://img.xkw.com/dksih/QBM/2017/10/10/1792123254161408/1792344241676288/STEM/3a53bd89e06a4e9aa54778c411cd43a0.png?resizew=185)
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】如图,在三棱锥
中,
⊥平面
,点P,M分别是
和
的中点,已知
,
,直线
与平面
所成的角为30°.
![](https://img.xkw.com/dksih/QBM/2024/1/25/3418618703503360/3419700500963328/STEM/a80e7a64126240678692ba1918391b49.png?resizew=185)
(1)求证:平面
⊥平面![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbc5ea3b02aa149ab24f9faa04339744.png)
(2)求二面角
的正切值
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2823bdb03fbdacb513498a41ac63b3d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5c9ca3af3eb8bc486f7b3f29f5065eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/787ac5e13622afab5e9f8603afe42356.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5c9ca3af3eb8bc486f7b3f29f5065eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ff6089095a8b825eeb8002b6996929e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a6fc026d474b8327e834ca0650b72be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daadcd54ede70b183d92857bc85cebf2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1165830b314a0dab65ea267e82bd3f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/787ac5e13622afab5e9f8603afe42356.png)
![](https://img.xkw.com/dksih/QBM/2024/1/25/3418618703503360/3419700500963328/STEM/a80e7a64126240678692ba1918391b49.png?resizew=185)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f26293ff841043aaf9e67c39f1fea6d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbc5ea3b02aa149ab24f9faa04339744.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a6b0b4cd6c9052a2afea4c897c1c5aa.png)
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解答题-问答题
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适中
(0.65)
解题方法
【推荐2】如图,几何体
中,正方形
所在平面与梯形
所在平面互相垂直,
,
,
,H为
的中点.
![](https://img.xkw.com/dksih/QBM/2020/10/22/2576706463588352/2577082551361536/STEM/3213537074ae45aa90f731a1c081482d.png?resizew=302)
(1)证明:平面
平面
;
(2)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9165d9bfbb0f0d19eb482c2a4c1b29b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b32c05247f6998d7a70d31d13be4148c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ddc5026db3720794fc689150541b741.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10df84d553a8826a7ce9bff4bf0d95b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea4f5eec0addba78f2e0cdfb7ecc59a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://img.xkw.com/dksih/QBM/2020/10/22/2576706463588352/2577082551361536/STEM/3213537074ae45aa90f731a1c081482d.png?resizew=302)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15f3e3f310f6ec3f3a26498e7ee17a00.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/630a21ba7a8e1b8bca73c1634cc6f74d.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/918c59422cf70719741b62f8664fe274.png)
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