名校
1 . 如图1,在四边形
中,
,
,
,将
沿着
折叠,使得
(如图2),过D作
,交
于点E.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/21/9bc8b8dc-8ded-4e5e-8520-df06cedcb6ce.png?resizew=296)
(1)证明:
;
(2)求
;
(3)求平面
与平面
的夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b512c0498d251e6859686c657b5be0ad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18120a244d3a1f9c1688bf53eb2ad775.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e32513c66bca1e2d1706d50a6615df1a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/661ff55b5ebbadfb600989af3cfce2fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bb5b12692517a39c320f99a479eb055.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec9e2a600d4675d510c58b984027e33d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/21/9bc8b8dc-8ded-4e5e-8520-df06cedcb6ce.png?resizew=296)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b757f0c42ae5c9a2d6a4b19e5877b27.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
(3)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c66d99a6a8415ddad22bbed33b64cfb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
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2024-03-07更新
|
395次组卷
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2卷引用:江西省部分重点中学2023-2024学年高二上学期期末联考数学试题(A卷)
名校
2 . 已知:在锐角
中,角
所对的边分别为
,
,
,且
,
;
(1)证明:
;
(2)若
边上的点
满足
,求线段
的长度的最大值.
![](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/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcb5bac75f36bb1dc5c8190d4dbe681d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/328cea739279f45f70a0e254ddd6983c.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5552651894bd1b81500b216586349dba.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2700a3103aef7c7cdb1ab54bf964639b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63a253c7fdf589ee3dece13d5b5b5732.png)
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名校
解题方法
3 . 在锐角
中,内角
所对的边分别为
,
,
,满足
,且
.
(1)求证:
;
(2)已知
是
的平分线,若
,求线段
长度的取值范围.
![](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/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ed5deb0e05a5f253ab198b4ccb54b8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f3c7849c21d8acdeda0f83b4f163457.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f44c181a2f6ae22d5d52b374768dc57.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d39b8d91afc34e4a9b0fdbb6bafb9087.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa4c355f11471a38f5583a434a1ddeb3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
您最近一年使用:0次
2023-08-12更新
|
2187次组卷
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13卷引用:浙江省嘉兴市秀水高级中学2022-2023学年高二下学期5月月考数学试题
浙江省嘉兴市秀水高级中学2022-2023学年高二下学期5月月考数学试题浙江省湖州、衢州、丽水三地市2023届高三下学期4月教学质量检测(二模)数学试题(已下线)数学(云南,安徽,黑龙江,山西,吉林五省新高考专用)(已下线)专题03 三角函数及解三角形(已下线)押新高考第17题 解三角形黑龙江省哈尔滨德强高中2022-2023学年高一下学期期中考试数学试题(已下线)模块二 专题3 解三角形与不等式河南省实验中学2023-2024学年高三上学期第一次月考数学试题(已下线)河南省实验中学2023-2024学年高三上学期第一次月考数学试题变式题15-18理科数学-【名校面对面】河南省三甲名校2023届高三校内模拟试题(五)(已下线)专题02 解三角形大题江苏省南通市2024届高三高考考前押题卷(最后一卷)数学试题2024届山东省五莲县第一中学高三模拟预测数学试题
4 . 在
中,角A,B,C所对的边分别是a,b,c,
,
,
.
(1)若
唯一确定,求m的值;
(2)设I是
的内切圆圆心,r是
内切圆半径,证明:当
时,
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e65397f11ea8af736f38debadf420c4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03837b3769eda7f0d3804cc5ad4a6d60.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d5738ee6a87acfffe81ac0f26610310.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
(2)设I是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33c0ad1334e7ac2a8159cc9824c75f20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e8e8a2d8447518d2b5083d5fd766374.png)
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名校
解题方法
5 . 在
中,角
,
,
的对边分别为
,
,
.
,
均为锐角,且满足
.
(1)证明:
是直角三角形;
(2)若
面积为
,求
的周长的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a848e6af9181dd6557ac1cd604f7e3c.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd3304e23f3b0f9569c4140ca89b6498.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
您最近一年使用:0次
2021-10-08更新
|
1331次组卷
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4卷引用:西藏拉萨那曲高级中学2021-2022学年高二上学期期中考试数学试题
西藏拉萨那曲高级中学2021-2022学年高二上学期期中考试数学试题2021年全国高考冲刺压轴卷(四)理科数学试题广西师范大学附属外国语学校2022届高三5月适应性模拟测试数学试题(已下线)拓展四:三角形周长(定值,最值,范围)问题 (精讲)(2) -【精讲精练】2022-2023学年高一数学下学期同步精讲精练(人教A版2019必修第二册)
名校
6 . 在△ABC中,内角A,B,C所对的边分别为a,b,c,已知cos2B+cosB=1-cosAcosC.
(1)求证:a,b,c成等比数列;
(2)若b=2,求△ABC的面积的最大值.
(1)求证:a,b,c成等比数列;
(2)若b=2,求△ABC的面积的最大值.
您最近一年使用:0次
2018-07-05更新
|
598次组卷
|
3卷引用:江西省新余市分宜中学2019-2020学年高二上学期第一次段考数学试题
名校
7 . 在
中,已知:
,且
.
(
)判断
的形状,并证明.
(
)求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5685c866bc9b79e86cfba9dd4779b89d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/497a307dbf92cb91fb04ebcdc8f6f558.png)
(
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
(
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67b292a8835d2b23ecc22bc2097eeb4f.png)
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2018-07-01更新
|
651次组卷
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7卷引用:2015-2016学年山东省临沂一中高二上学期期中考试理科数学试卷