如图,在四棱锥
中,
底面
,
,点
在
上,
,过点
作
的垂线交
于点
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/23/0f2a09fe-1071-4499-b752-3aee78e05a42.png?resizew=153)
(1)证明:
平面
;
(2)求平面
与平面
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5164a3cc47e266446d49127e2ef10c37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f4c3f9dd5d0343597a7f58a1989b537.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e60af2ff39cfdc2335996c51f8be677.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f341b98caabf99bc683ce8407068735e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1496042c1d721cffd25053e997a9a97.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/23/0f2a09fe-1071-4499-b752-3aee78e05a42.png?resizew=153)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a22d6b860f06fe23618b0d3de6768fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73cc4309dcef077fbcf60099f47b7b37.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73cc4309dcef077fbcf60099f47b7b37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
更新时间:2024-02-23 18:07:32
|
相似题推荐
解答题-证明题
|
适中
(0.65)
名校
【推荐1】如图,在三棱柱
中,每个侧面均为正方形,
为底边
的中点,
为侧棱
的中点.
![](https://img.xkw.com/dksih/QBM/2010/4/30/1569709890617344/1569709895819264/STEM/7e3a0ed72a6a48609bb2507307d60975.png?resizew=185)
(Ⅰ)求证:
∥平面
;
(Ⅱ)求证:
平面
;
(Ⅲ)求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://img.xkw.com/dksih/QBM/2010/4/30/1569709890617344/1569709895819264/STEM/7e3a0ed72a6a48609bb2507307d60975.png?resizew=185)
(Ⅰ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/641d9688e81760c02d0dfc4ba015afb1.png)
(Ⅱ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4560fa4ad459b58b723c74bd24e51ebf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/641d9688e81760c02d0dfc4ba015afb1.png)
(Ⅲ)求直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f1158eaa2e338f564eb18de5bef1d25.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ac61c24f99a4e466f1e2ea011893866.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,四棱锥
的底面为正方形,
底面
.设平面
与平面
的交线为
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/2/8eca6df1-1e8c-43dc-a8a3-3dc897b5214b.png?resizew=214)
(1)证明:
平面
;
(2)已知
,
为
上的点且,
,求
与平面
所成角的正弦值的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a1b49f64e0065edad868b25e9fcada3.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/e7b7c83470489253394bd288d7c920df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/2/8eca6df1-1e8c-43dc-a8a3-3dc897b5214b.png?resizew=214)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9df740160690029ac1e730c85f20347.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/218054144a13435580cd132b9459546c.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b624742fe28db114e0554c6c87bff05c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6943e6e7640e2b6113fcc870c2704b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c550269f3199038726f55cbd281c13a.png)
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解答题-证明题
|
适中
(0.65)
名校
【推荐3】已知正四棱柱
中,
,
.
(1)求证:
;
(2)在线段
上是否存在点
,使得平面
平面
,若存在,求出
的值;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e55a2310cbba5e050488cd9296eb195d.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/417104247ce266ae42c3a9860f387272.png)
(2)在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc492b4bf027e8eeba9c08ecebb50f4c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f571a1aac46c6d0cf440c0ec2846bf9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfa70b6554a9c50365435afc5742193c.png)
您最近一年使用:0次
解答题-证明题
|
适中
(0.65)
【推荐1】如图,在几何体
中,底面
是平行四边形,
,
,
平面
,
与
交于点
.
![](https://img.xkw.com/dksih/QBM/2018/4/24/1930857410142208/1934331390058496/STEM/fbd04872757c4943a4753c35dd03d4c5.png?resizew=324)
(1)求证:
平面
;
(2)若平面
与平面
所成的锐二面角余弦值为
,求线段
的长度.
![](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/5f79863ffcfa63117ca6741b20a48e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93aeb3aab3e021beacfc369510365440.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4c5ae16a7145a28a91d45ef950a07c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b32c05247f6998d7a70d31d13be4148c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d004d2d115b477ade6af7ddb93db0df8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://img.xkw.com/dksih/QBM/2018/4/24/1930857410142208/1934331390058496/STEM/fbd04872757c4943a4753c35dd03d4c5.png?resizew=324)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d38e752c16ae27d35378a765172022b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4734735213b599a9915e1ed91a5d8ce4.png)
(2)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b1859fdfd4e3d3c98c5e41dcc27224f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c93a34cbd4c0dc198b74524c0e05a10.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38cb57b942813635ef4e4c3bea67928f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d97dc3b752832906de41447bb58a341.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐2】已知正方形
的边长为2,沿
将
折起到
的位置(如图),
为
的重心,点
在边
上,且
.
![](https://img.xkw.com/dksih/QBM/2022/3/9/2932408211038208/2933921439539200/STEM/191b47ca-f293-49fa-8125-117f3c5e575e.png?resizew=268)
(1)证明:
平面
.
(2)若
,求平面
与平面
所成锐二面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acee03d4bb4667b6c345221b6c9b0fa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acee03d4bb4667b6c345221b6c9b0fa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39e7b83a2497d1662d1a95ec4cbb7495.png)
![](https://img.xkw.com/dksih/QBM/2022/3/9/2932408211038208/2933921439539200/STEM/191b47ca-f293-49fa-8125-117f3c5e575e.png?resizew=268)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a227bcc7ee91e914c0c6bec05f82b0e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bd71a51335c84d58f07db304d86092a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6734b2bef8750392d3c5c08b5d878505.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
您最近一年使用:0次