如图,三棱柱ABC-A1B1C1的底面是边长为4的正三角形,AA1⊥平面ABC,AA1=2,M为A1B1的中点.
(1)求证:MC⊥AB;
(2)在棱CC1上是否存在点P,使得MC⊥平面ABP?若存在,确定点P的位置;若不存在,说明理由.
(3)若点P为CC1的中点,求二面角B-AP-C的余弦值.
更新时间:2018-01-10 09:14:29
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
【推荐1】如图,四棱锥
是底面边长为
的正方形,
,
,
.
![](https://img.xkw.com/dksih/QBM/2021/1/26/2650826602856448/2654269982007296/STEM/43ce6f3d5dd04d46b5276444eb134192.png?resizew=158)
(1)求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
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/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c65334978b0519b379910dfc4acf8344.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41cd5c4f8b106d01e0e431078e1a468b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2ced8225ff27c8e3e1897b8629312d5.png)
![](https://img.xkw.com/dksih/QBM/2021/1/26/2650826602856448/2654269982007296/STEM/43ce6f3d5dd04d46b5276444eb134192.png?resizew=158)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1633988fd62a652de726ee92a917b52d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1047ac90668f2e8eafbc26afe983b756.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】在三棱柱ABC-A1B1C1中,AC=3,CC1⊥平面ABC,BC=4,AB=5,AA1=4,点D是AB的中点.
(2)求证:AC1∥平面CDB1.
(2)求证:AC1∥平面CDB1.
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐3】如图,四边形ABCD是圆柱OQ的轴截面,圆柱OQ的侧面积为
,点P在圆柱OQ的底面圆周上,且三角形OPB是边长为
的等边三角形,点G是DP的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/27/8650075c-68a4-4df9-b462-56f3703c2872.png?resizew=195)
(1)若G是DP的中点,求证:AG⊥BD;
(2)若
,求GB与平面ABCD所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d022501bbc946a88d43d38a43ec2c8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7ffe8515ff6183c1c7775dc6f94bdb8.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/27/8650075c-68a4-4df9-b462-56f3703c2872.png?resizew=195)
(1)若G是DP的中点,求证:AG⊥BD;
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9de4967f473cd4affb1a43de35b9a4cf.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
名校
【推荐1】如图,在四棱锥
中,
//
,
,
,且
与
均为正三角形,
为
的中线,点
在线段
,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/26/5c385e43-ec03-4e48-a4cf-a2235a3f5fe1.png?resizew=164)
(1)求证:
//平面
;
(2)若平面
平面
,求平面
与平面
所成锐二面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.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/2f8cfaf72b97aa690ff41c84f9ed29a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d0d5f57a40474205aee752e23ec449d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55a675310c8ba418e5a59beb7317e21e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55a675310c8ba418e5a59beb7317e21e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75fc32d55aca2289a49a67804b338c9e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/26/5c385e43-ec03-4e48-a4cf-a2235a3f5fe1.png?resizew=164)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0e57a13c665af88f326c9890072bf73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/218054144a13435580cd132b9459546c.png)
(2)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e78f6e09cc900502f9113e8a32e19899.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,在三棱锥
中,
,
,
为点
在平面
的射影,
为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/7/aca4fd47-38e0-4342-8b90-885fb44eeea4.png?resizew=164)
(1)证明
平面
;
(2)若
,
,
,求平面
与平面
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c41ffdaecfb3c73d403179e5745c71a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3570a95f68349fcd9417fcda62e78e7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1326e85ff750d882de9ea65c29e3d3b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/7/aca4fd47-38e0-4342-8b90-885fb44eeea4.png?resizew=164)
(1)证明
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d85f14d046c7d50a349b9c1fcf717d1b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7abd284f76d9f5769bc189508ce2572b.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f08273d339dc5ddbb89aa67bb8205e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f26e32412868f3dcb5cad62c8a836778.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac6edb7e5ea744db95ac422fe2e2af3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af68a7bf0da4f7c6f739d2e2461ad9b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9df915a088300b53c298fecd10675e5b.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐3】某几何体是上、下底面均为扇环形的柱体(扇环是指圆环被扇形截得的部分),其中
均与底面垂直,底面扇环对应的两个圆的半径分别为1和2,对应的圆心角为
,E为弧
的中点.
(1)证明:
平面
.
(2)直线
与
所成角的余弦值为
.
(i)求直线
与平面
所成角的正弦值;
(ii)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/360a93b9662f0ab8a69b131497520b53.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84288b493b64c3a30466fb9075621da4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/394c5d2f55221975503be8aa18022480.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/307807ee10071bafbe922eb18d2517d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e4755dc59cb5a03cd39879bc80fdbb9.png)
(2)直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b470c4e195cf7a07b7a331ce4b436e03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e539f26ed5e0b20ff7220559324869a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f558992e649b93ee36f37513781311a8.png)
(i)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b470c4e195cf7a07b7a331ce4b436e03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e4755dc59cb5a03cd39879bc80fdbb9.png)
(ii)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3a34ca15cac631d71e071408d54550c.png)
您最近一年使用:0次