1 . 如图,在正方体
中![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54e1d0f65817ba32a732040518f41440.png)
(1)求证:面
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/54e1d0f65817ba32a732040518f41440.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/19/25285258-74d3-4493-8949-5bf190437ef4.png?resizew=149)
(1)求证:面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86ff92a552f29d890125165c894db126.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a211ad5a06b505b8365a62c1946f3cb7.png)
(2)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cfa4c2dcb9bb6b53f37e7241186a189b.png)
您最近一年使用:0次
2023-07-16更新
|
418次组卷
|
2卷引用:新疆乌鲁木齐市五校2022-2023学年高二下学期期末联考数学(文)试题
名校
解题方法
2 . 已知
的内解
所对的边分别为
,满足
.
(1)求证:
;
(2)若
为
上一点,且
,求
的面积的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1db789b3e162dc967f1fb1dc58a988fa.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/baa8d75a6638e08eedbff8662267da6f.png)
(2)若
![](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/df01d40611ad128b314244ac8090cd95.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ac451db3443cabb204f96c31fd4a02e.png)
您最近一年使用:0次
2023-07-16更新
|
584次组卷
|
2卷引用:广东省汕头市金山中学2023-2024学年高二上学期10月阶段考试数学试卷
3 . 如图1,已知正三棱锥
分别为
的中点,将其展开得到如图2的平面展开图(点
的展开点分别为
,点
的展开点分别为
),其中
的面积为
.在三棱锥
中,
(1)求证:
平面
;
(2)求平面
与平面
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a78432c0302b041c04b5f4d78cedde1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/374fe9986ebbc986fc422e514ab93a51.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5425108c557f0f21474c045334f97d9c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05df617dae0d3203f02a488277e419f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2793a649954fbb40a20100114cc507f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b27567d43c5b91382ee3d7ca708ee422.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/12/29faa8bd-8d34-47af-a14a-e24dd980c84d.png?resizew=246)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f9157fce2a8339d281178c7c0bccbe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c5757f787d98f9a46777324b69ad672.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22ce50ba5e349425274f05d46d120a74.png)
您最近一年使用:0次
4 . 已知在
中,D是BC边上一点.
(1)若
,
,
,求证:
;
(2)若
,
,
,
,BC边的长大于4,求
的面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4376af85e07b29051a812ff3fcda61a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a70c01e50e1f515598300f18278324a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4b85155ef02a3d4ad84819e14d0c12a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ead64391e42f81943e500aed314e4b4.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55493e331f88d3d1c396e92b46c97ecd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16e0c5cb53fd85b7a23f0580df6bb49a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4fc2d383876afe5be1103352571805b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dfb08f6a798dc293f3d8de281190f65e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ac451db3443cabb204f96c31fd4a02e.png)
您最近一年使用:0次
名校
解题方法
5 . 记
的内角
的对边分别为
,已知
,且
.
(1)证明:
;
(2)若
为锐角三角形,且
,求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0796c1519cdd91eb2c1762c6a3c54419.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad5e009486af263893ca8290be72f258.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59dd4c6a344ae3c8d5a6f2b875015467.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f44c181a2f6ae22d5d52b374768dc57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
您最近一年使用:0次
2023-07-07更新
|
569次组卷
|
4卷引用:湖南省五市十校教研教改共同体、三湘名校教育联盟、湖湘名校教育联合体2022-2023学年高二下学期7月期末联考数学试题
6 . 如图,梯形
中,
,
,
,沿对角线
将
折起,使点B在平面
内的投影O恰在
上.
(1)求证:
平面
;
(2)求异面直线
与
所成的角;
(3)求二面角
的平面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/829018a6ca0aff95d89e3f7cd943274e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09d27bd71d79cb19eb554175e4ef0867.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4182c37d2bad62dda4f901432ef9482.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/4/7bdaa6fc-5a15-4c24-a8e7-e00e68922fec.png?resizew=322)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21f9157fce2a8339d281178c7c0bccbe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
(2)求异面直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
(3)求二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd29cc627d76412c236aac6b29fa0fdf.png)
您最近一年使用:0次
7 . (1)求
的值.
(2)求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79924347bba3fb0d5d4b8cddba605ce6.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/40741686c62be2f272e2f2ced4febbfe.png)
您最近一年使用:0次
8 . 在四棱锥
中,
为正三角形,四边形
为等腰梯形,
为棱
的中点,且
,
.
(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/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2205cffebf8c4d5f81d15ed7b85c8936.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19d5323016483af9d1fca72486942e85.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6560043276739bbd99cd5064b6182f1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/24/3ea66b2d-6335-4d31-8546-473d74dfada9.png?resizew=153)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19ad6a0124359e8b9f7649cf0bff51ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
您最近一年使用:0次
解题方法
9 . 已知在△ABC中,角A,B,C的对边分别为a,b,c,且
.
(1)求C;
(2)若c=2,△ABC的面积为
,求证:△ABC是正三角形.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc6c1ebbba9416bec429df39eb214ce6.png)
(1)求C;
(2)若c=2,△ABC的面积为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7ffe8515ff6183c1c7775dc6f94bdb8.png)
您最近一年使用:0次
2023-06-21更新
|
380次组卷
|
2卷引用:河南省焦作市2022-2023学年高二下学期期末数学试题
名校
解题方法
10 .
中,角A,B,C的对边分别为a,b,c,且
.
(1)求证:
;
(2)若
,试求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d00c05c8a29672eab68eb17da0a52bc7.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fefb66baf2c738593be618b5895c4975.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2157af46e8e67ded9b418752a1faf658.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c046006255071ed05f2658cf6f9519e1.png)
您最近一年使用:0次