解题方法
1 . 如图,已知侧棱垂直于底面的四棱柱
中,
,
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/13/7e1fe7ea-9f36-46dd-9fac-92de6060f7db.png?resizew=141)
(1)若
是线段
上的点且满足
,求证:平面
平面
;
(2)求二面角
的平面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d262480ffb55b7617f44b63f130c154a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ea82794c0cf262948c38aa776f4b059.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87b2f446cccf2652c090e99a75beb3bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/295640e886a3a29c5159a93fa287ee68.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/13/7e1fe7ea-9f36-46dd-9fac-92de6060f7db.png?resizew=141)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a696a182fff038a86b2bbe8ca099442.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8585f248084f3ed36109299301e4f129.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e54cf75bbfc9db93d27937c8b8e977b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73845d4d663b3de0b281611fe2c762fe.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b349fce5141b5b10ae82da7a49f0e9c7.png)
您最近一年使用:0次
名校
2 . 如图,已知长方形
中,
,
,
为
的中点.将
沿
折起,使得平面
平面
.
(1)求证:
;
(2)若点
是线段
上的一动点,问点
在何位置时,二面角
的余弦值为
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080ca48cd27d4bf9d9ef084b558fc17a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a88c44f558705de3bcefcfc0ece96b8f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e52a8f07834cbbbe4224962672fbbb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7f9fba8a4098c1a0515286eb8d616dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0bb5012f6c70a1e98d682b6d021fadd8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0760712e3e2ea02b755b751e760d0c55.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/804c0e2a375b5f4ff1c420532968efc3.png)
(2)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d97dc3b752832906de41447bb58a341.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a5266895d3c1fcb350a745bc779433b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d5989c84e320b504511f23eeb6e7357.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/20/e2b38925-14e6-49c4-af18-03066b6e9cad.png?resizew=363)
您最近一年使用:0次
2017-05-03更新
|
608次组卷
|
3卷引用:广西百色市平果市铝城中学2024届高三上学期摸底考试数学预测卷(一)
3 . 如图,在各棱长均为4的直四棱柱
中,底面
为菱形,
,
为棱
上一点,且
.
(1)求证:平面
平面
;
(2)求二面角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f945a69cf7e8213e50622125cde652f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/694fc1d576562f85acd2f157818f97cd.png)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8dc6db50a9709c3f4d84eee7bdf1250.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2bf9ef324f1289e205e29fed105c38e.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3deaf03eb9e66570c9856d7360b6a76c.png)
![](https://img.xkw.com/dksih/QBM/2017/5/19/1690281881608192/1691608625373184/STEM/4559b1c6e796478ea1a2c3ccb533ee9e.png?resizew=144)
您最近一年使用:0次
2017-04-27更新
|
499次组卷
|
2卷引用:广西2017届高三5月份考前模拟适应性联合考试数学(理)试题
名校
解题方法
4 . 已知五边形
是由直角梯形
和等腰直角三角形
构成,如图所示,
,
,
,且![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07a528b9d6407fe54c63a08d2c2e8093.png)
,将五边形
沿着
折起,且使平面
平面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/10/a473ef15-f91b-4457-9293-cb27f73eabcf.png?resizew=242)
(1)若
为
中点,边
上是否存在一点
,使得
∥平面
?若存在,求
的值;若不存在,说明理由;
(2)求二面角
的平面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9142a8490de14a87eda628ffa7e28982.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9a32bd7a1b78b5a0ec562c4025aea8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1134c8e3440abb6cd385af2c169037fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d5427b7b994b860628df3d6b7a07de8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a11029ca6b4b9e7f777af0280cf163c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07a528b9d6407fe54c63a08d2c2e8093.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24e406d914443fe50297f375347be10.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9142a8490de14a87eda628ffa7e28982.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cf9a6db3571fa57bfa2d5e4d44c51b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9a32bd7a1b78b5a0ec562c4025aea8c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/10/a473ef15-f91b-4457-9293-cb27f73eabcf.png?resizew=242)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c09afc70f448545336304333d5b5658b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48732e80ec3c3b6de906d598c69840d5.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a351d71fa01d3f5920e374a8ee7b524.png)
您最近一年使用:0次
2017-04-17更新
|
522次组卷
|
2卷引用:广西壮族自治区玉林高中2017届高三高考冲刺模拟(十)数学(理科)试题
5 . 如图,四棱锥
底面为正方形,已知
,
,点
为线段
上任意一点(不含端点),点
在线段
上,且
.
(1)求证:
;
(2)若
为线段
中点,求直线
与平面
所成的角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d02bd5cfe804460846423e77f72db10f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/739cf9d6398614ee0811671c5f2e2e2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4766453a574acb88989d6f342f8a867.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e61620a272dada8d4b9a9fab6379dfd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3182db896bc2462331796e2a6108363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/641202ef2a3cca2ced852be29baf1f6c.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83ec065906f44557ce20e135191275b3.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e61620a272dada8d4b9a9fab6379dfd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30513ea48bc1ef3ae78adac83d894f14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e867e5eac6de1647a9ede91ffa083f4a.png)
![](https://img.xkw.com/dksih/QBM/2018/2/28/1892134415482880/1895790200430592/STEM/5acc9bd3e8fe4eff8b0f6990aee79ef5.png?resizew=161)
您最近一年使用:0次
2017-04-15更新
|
1005次组卷
|
6卷引用:广西钦州市2018届高三上学期第一次质量检测数学(理)试题3
6 . 如图,在多面体
中,底面
是边长为2的菱形,
,四边形
是矩形,平面
平面
.
(1)在图中画出过点
的平面
,使得
平面
(必须说明画法,不需证明);
(2)若二面角
是
,求
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9165d9bfbb0f0d19eb482c2a4c1b29b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6906f59d09ce31956d6f5ea2b23fc77.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f84f169e50dc59d4f7a8e1e36f5c847.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1b6711e6dd48be6cf8fa52926924d21.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(1)在图中画出过点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbdb21011ea821b91d539cb763aac649.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87a60be170a52db82cf37b30db0cde26.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b03428a8f91a5674cb8f54766c165f7e.png)
(2)若二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d2fd494ec8c370a22ae16699eac4cff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1e5fa72f2878b476bc57f0df12d6555.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2319a01218514917e446dfc807a625ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/30/88270266-0236-44d8-9a0f-f9037646233d.jpg?resizew=140)
您最近一年使用:0次
2017-04-13更新
|
879次组卷
|
2卷引用:2017届广西桂林市、崇左市、百色市高三下学期第一次联合模拟(一模)考试理数试卷
名校
解题方法
7 . 如图,在直三棱柱
中,
,
,
,
是线段
上一点,且
平面
,则直线
与
所成角的余弦值为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bb5b12692517a39c320f99a479eb055.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6e55b54a13f8a9f66fdf9d0ff7cf82e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/077c956ac0eb05cf120e14f17413dfa2.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/02cb62f4c1e0e023619922eb8a509c98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbc7e774e4ae40c23bf4ceed179230ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://img.xkw.com/dksih/QBM/2017/3/7/1638704566247424/1656268033146880/STEM/76fffac0264f477c9492e2a395e3092e.png?resizew=184)
您最近一年使用:0次
名校
8 . 如图所示,三棱柱
中,已知
侧面
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/26/0f91ce32-1609-4413-8e4d-0c1d9edcf53f.png?resizew=202)
(1)求证:
平面
;
(2)
是棱长
上的一点,若二面角
的正弦值为
,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f9157fce2a8339d281178c7c0bccbe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e8818d8a5556ae25b34bd4321e3ea64.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/26/0f91ce32-1609-4413-8e4d-0c1d9edcf53f.png?resizew=202)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/231673dd67ab79d3c5da73904ceade1e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c6e8e9849324ec92b33bed5f44562e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4eedae8d316c76e3d0b451256de03fb9.png)
您最近一年使用:0次
2017-03-23更新
|
1166次组卷
|
6卷引用:广西柳州高级中学、南宁市第二中学2018届高三上学期第二次联考数学(理)试题1
广西柳州高级中学、南宁市第二中学2018届高三上学期第二次联考数学(理)试题1广西柳州高级中学、南宁市第二中学2018届高三上学期第二次联考数学(理)试题2湖南省长沙市第一中学2017届高三高考模拟卷一理科数学2017届辽宁省沈阳市省示范协作校高三第一次模拟考试数学(理)试卷(已下线)2017-2018学年第一学期期末复习备考之精准复习模拟题高三年级(理)人教版数学试题(C卷)天津市第一中学2018届高三上学期第三次月考数学(理)试题2
名校
9 . 在四棱锥
中,
,
,
和
都是边长为2的等边三角形,设
在底面
的射影为
.
![](https://img.xkw.com/dksih/QBM/2017/3/6/1637836815663104/1637860221419520/STEM/9f3f9bef-f847-4992-9bc4-4e514e3a462c.png?resizew=184)
(1)求证:
是
中点;
(2)证明:
;
(3)求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db08db31046bf98eb01abfbf356059ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c235aa3c3d273fdf205b1057eea7439.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2205cffebf8c4d5f81d15ed7b85c8936.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acee03d4bb4667b6c345221b6c9b0fa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://img.xkw.com/dksih/QBM/2017/3/6/1637836815663104/1637860221419520/STEM/9f3f9bef-f847-4992-9bc4-4e514e3a462c.png?resizew=184)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da48240e7fc3248f773ac1500c15ec14.png)
(3)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b33b7213d99a817bff19bcf740a0697c.png)
您最近一年使用:0次
2017-03-06更新
|
883次组卷
|
5卷引用:2017届广西柳州市、钦州市高三第一次模拟考试理数试卷
10 . 如图,在三棱柱
中,侧面
与侧面
都是菱形,
,
.
![](https://img.xkw.com/dksih/QBM/2017/3/17/1645868167618560/1647832324243456/STEM/fac891dc2c09494580c5bb3d31671a57.png?resizew=245)
(1)求证:
;
(2)若
,
的中点为
,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d9a8181f7a7fe7f3fac872ce9534f15.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee8b5a6dbcf05f572f83f51abf7d668c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5527d593955c156a0e96a2dc9d382333.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e1f4f255d191786f7d330d278868c2d.png)
![](https://img.xkw.com/dksih/QBM/2017/3/17/1645868167618560/1647832324243456/STEM/fac891dc2c09494580c5bb3d31671a57.png?resizew=245)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82c2b3adb41e8965f553da2e5086a751.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56e7e971db98894c4dbab6848ff47b51.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f1f229274a6e17977cc047814212589.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6795cae2df43a722e1355e9562d93c09.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2301994812f900c1a2dbdc9a0affaab.png)
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2017-02-18更新
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3卷引用:2017届广西高三上学期教育质量诊断性联合考试数学(理)试卷