四棱锥
底面是菱形,
⊥平面
,
,
、
分别是
、
的中点.
![](https://img.xkw.com/dksih/QBM/2016/9/13/1573017026134016/1573017032065024/STEM/74e2360f80634cdabd5d36c63fc0b63c.png?resizew=195)
(1)求证:平面
平面
;
(2)若
,设
为
的四等分点(靠近点
),求
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/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05740f0c6071846227dc0ec177ad15e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://img.xkw.com/dksih/QBM/2016/9/13/1573017026134016/1573017032065024/STEM/74e2360f80634cdabd5d36c63fc0b63c.png?resizew=195)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6501f1c913a4ef64957a2f01ab5baa15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/757a339391bc1c8e64df82a26ee965b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/589786dd7c3a2679c3230b671cd232d6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b03428a8f91a5674cb8f54766c165f7e.png)
更新时间:2016-12-04 20:14:15
|
相似题推荐
解答题-证明题
|
适中
(0.65)
解题方法
【推荐1】如图1,在
中,
,
,点
,
分别为
,
中点,
,
交于点
,
,如图2,把
沿
折起,
,
分别到达
,
,
,
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/12/7ec58bd7-d81f-43a3-bd8a-daa3ac85e852.png?resizew=283)
(1)求证:平面
平面
;
(2)求平面
与平面
所成锐二面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c1ac2e11788860424508ea9e80cf89d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.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/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.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/d70834818750d0454474ac7c357cd287.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e742966e3711cfa53dce04022acf4bcc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/473f1a9e2efae74a9b1a140126f76d34.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/12/7ec58bd7-d81f-43a3-bd8a-daa3ac85e852.png?resizew=283)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d76f02bc710aa27add73b740ca4e3547.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9a814b70236a108be5d6e7ff271fe92.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1b489c25405ce48699d4f0a62820bed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3397fad1693129c42d5dd1b25e87e6de.png)
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解答题-证明题
|
适中
(0.65)
名校
【推荐2】如图所示,在四棱锥P-ABCD中,底面是边长为a的正方形,侧棱PD=a,PA=PC=
a,
(1)求证:PD⊥平面ABCD;
(2)求证:平面PAC⊥平面PBD;
(3)求二面角P-AC-D的正切值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf298f00799cbf34b4db26f5f63af92f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/17/aca92b55-ded7-4c97-862a-94d87df5851d.png?resizew=134)
(1)求证:PD⊥平面ABCD;
(2)求证:平面PAC⊥平面PBD;
(3)求二面角P-AC-D的正切值.
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解答题-证明题
|
适中
(0.65)
解题方法
【推荐1】如图,在多面体ABCDEF中,四边形ABCD与ABEF均为直角梯形,
,
,
平面ABEF,
,AD=AB=2BC=2BE=2.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/30/949ff85f-742a-4afd-bfe2-da337373aa2a.png?resizew=151)
(1)已知点G为AF上一点,AG=AD,求证:BG与平面DCE不平行;
(2)已知直线BF与平面DCE所成角的正弦值为
,求点F到平面DCE的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4adf90a8c2b29334cdc5aa5b554991f9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d61d846cbc5220533271c962b85c4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd654221ab95fe241d9e0202443f2609.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eed15d0ed75bf936f224f931da5d950.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/10/30/949ff85f-742a-4afd-bfe2-da337373aa2a.png?resizew=151)
(1)已知点G为AF上一点,AG=AD,求证:BG与平面DCE不平行;
(2)已知直线BF与平面DCE所成角的正弦值为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dee14db57f0c762aad845cf5b4a243c0.png)
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解答题-问答题
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适中
(0.65)
【推荐2】如图,三棱锥A-BCD中,
,O为CD中点,平面AOB⊥平面BCD.![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56ee81929c987732fcb379802eeef7a7.png)
(2)若三棱锥A-BCD的体积为
,二面角
的余弦值为
,E为BC中点.求BD与平面AED所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09bf10480aa8c1ba4fbfc22b21230bda.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56ee81929c987732fcb379802eeef7a7.png)
(2)若三棱锥A-BCD的体积为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf31876698721a199c7c53c6b320aa86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca6d1c5eace748465b2dad5065f5111c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dee14db57f0c762aad845cf5b4a243c0.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
名校
【推荐3】如图,在四棱锥
中,底面
是平行四边形,
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b2890ace2b153b9eaf2cbc523b8211d.png)
,
分别为
的中点,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/21/e2559b3f-eb17-4a2a-ad0c-61a353fe67d4.png?resizew=164)
(1)证明:
平面
;
(2)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/c6351de5d5e1176f5f9bde4c5bffda6b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b2890ace2b153b9eaf2cbc523b8211d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7102372a92801ac35bba16bd54020e0f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b1683fed718259fa7b77ced8be46c87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a8b76f93f1609f49e5d85fd8b5db004.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/21/e2559b3f-eb17-4a2a-ad0c-61a353fe67d4.png?resizew=164)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a7442b64b37f685bc3ae88ff450c1a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f50b3ae183997b707d16eb4e7f6712fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
您最近一年使用:0次