名校
1 . 在
中,角A的平分线交线段
于点D.
![](https://img.xkw.com/dksih/QBM/2021/5/28/2730716921061376/2735291852570624/STEM/d1f7dd00-48e0-415e-bfe6-54a59f3929e5.png?resizew=246)
(1)证明
;
(2)若
,
,
,求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://img.xkw.com/dksih/QBM/2021/5/28/2730716921061376/2735291852570624/STEM/d1f7dd00-48e0-415e-bfe6-54a59f3929e5.png?resizew=246)
(1)证明
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea5ca418ff0d36929cd06551f74d58c2.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/305a88d4e0249bd16d48eda01331d2d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4494a85de0be0b97a69348115aef8513.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dae8221601c7bd5c51fd520615581fa1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
您最近一年使用:0次
2021-06-03更新
|
1094次组卷
|
3卷引用:福建省三明第一中学2021届高三5月校模拟考数学试题
2 . 已知等边三角形
分别是边
上的三等分点,且
(如图甲),将
沿
折起到
的位置(如图乙),
是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/18/fee79488-59ec-4eb1-9cf0-973366d5735d.png?resizew=399)
(1)求证:
平面
;
(2)若二面角
的大小为
,求直线
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42ab05980824d7403b26cc3d3aa5436f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dec2ca6438c82b43f746057d8129885.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d42218a68301d770accaaefb96b19f8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3aa2a83fed9bf4cb09d84a980452e346.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10d8eb4a9f462ca0c1d49c3fe91e720d.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/18/fee79488-59ec-4eb1-9cf0-973366d5735d.png?resizew=399)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd0285afe567ca0b32f0ccafc30167cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9afac7c616bbb14e1ed428a3c507c7dc.png)
(2)若二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/628d6fc46c651e0c783b81a123a7b229.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f785147690f83dcee0a0bc6c327e75a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a98287a302228ece1fa53c5c66c590f.png)
您最近一年使用:0次
名校
解题方法
3 . 在
中,角
所对的边分别为
,
.
(1)求
;
(2)点
在
外,
,
,若四边形
的面积为
,证明:四边形
为梯形.
![](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/95d37b2f8d5da8eaa07442b941017c1c.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
(2)点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5679a74e9f5506266ab627894ab03243.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae139b51956b9281d73d9ba82b875e46.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2ca820a456491348e72587e4fe10bc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
您最近一年使用:0次
2021-06-07更新
|
502次组卷
|
2卷引用:福建省厦门市2021届高三5月二模数学(A卷)试题
名校
解题方法
4 . 在
中,内角
,
,
的对边分别是
,
,
,若
,
.
(1)求角
;
(2)若
为
的角平分线,证明:
.
![](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/e65397f11ea8af736f38debadf420c4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/faaeeac3ad7c1946c4ebfb17a49e2e31.png)
(1)求角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b6e1e4294a8d83e0119ac5e91af71d4.png)
您最近一年使用:0次
解题方法
5 . 已知
,
,
分别是
的三个内角
,
,
的对边,且![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29b55705126ccc1fa39c1061854eb99b.png)
(1)求证:
;
(2)若
,求
.
![](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/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/29b55705126ccc1fa39c1061854eb99b.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe29c42302504e7fd8577dbc7d130ac7.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/850e2bc625eca71b12044de26db2fa3a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
您最近一年使用:0次
2021-01-29更新
|
181次组卷
|
2卷引用:福建省厦门市国祺中学2024届高三上学期第一次月考数学试题
名校
解题方法
6 . 如图1,在平面四边形
中,
,
,
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/25/a5ae3edb-8e5a-4cfe-9403-1063f4c46f11.png?resizew=105)
(1)求
;
(2)将
沿
折起,形成如图2所示的三棱锥
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/25/4c338fd5-8403-4a98-bfa2-c74bb9d186ba.png?resizew=193)
①三棱锥
中,证明:点
在平面
上的正投影为点
;
②三棱锥
中,点
分别为线段
的中点,设平面DEF与平面
的交线为
,
为
上的点.求
与平面
所成角的正弦值的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/520f8abda6a85e7ef6f281fc2df853fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/681e755d65c534cd8e8dda38d710673f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2bff08f5a504769605dbb6259dfc3a0.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/25/a5ae3edb-8e5a-4cfe-9403-1063f4c46f11.png?resizew=105)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97c72f90816b60644129bab04e1e9c60.png)
(2)将
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/661ff55b5ebbadfb600989af3cfce2fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3df55d7d8744aa5e253d4fa026163d5.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/25/4c338fd5-8403-4a98-bfa2-c74bb9d186ba.png?resizew=193)
①三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4357d5744046d4d44abb09e1ee35fcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
②三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4357d5744046d4d44abb09e1ee35fcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b199a99e53d67ff4abf233930961a29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a0e08a39c6619123557148d195abfbe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8010e1a73f05117a278860c1c0c7f147.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.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/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16cbfc100b8219ba98c91e911f4d5329.png)
您最近一年使用:0次
2020-12-06更新
|
893次组卷
|
4卷引用:福建省泉州市第九中学2023届高三下学期第一次月考数学试题
名校
解题方法
7 . 在平面直角坐标系
中,已知以点
(
)为圆心的圆过原点O,不过圆心C的直线
(
)与圆C交于M,N两点,且点
为线段
的中点.
(1)求m的值和圆C的方程;
(2)若Q是直线
上的动点,直线
,
分别切圆C于A,B两点,求证:直线
恒过定点;
(3)若过点
(
)的直线L与圆C交于D,E两点,对于每一个确定的t,当
的面积最大时,记直线l的斜率的平方为u,试用含t的代数式表示u,并求u的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee31829d0d4d5f779a957d7df8058ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8364328956b993b4774d65e4287fdee5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94440d3e4c073f94f2b266ff99d50e74.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe31f22a77fd0ad51788f5642d72425d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcd9218a657b17654c5d757a6f7dee9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ecae6ad8fd8a0178479b0761ba76d391.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411461db15ee8086332c531e086c40c7.png)
(1)求m的值和圆C的方程;
(2)若Q是直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd24f3c4bc9f9a75d4b28630bb630d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0bf25e032b5599ac49383de06e776365.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf702adb116c1e46569eb7050d029f49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
(3)若过点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18704146ef2e010ebf1e70041d8766da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dbdec563cc725687b7abaf1d5973b955.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d631f45bc652539853f236952afa5bbf.png)
您最近一年使用:0次
2020-09-17更新
|
1120次组卷
|
6卷引用:福建师范大学附属中学2020-2021学年高二上学期期中考试数学试题
福建师范大学附属中学2020-2021学年高二上学期期中考试数学试题广东省广东实验中学2019-2020学年高一下学期期中数学试题天津市南开中学2020-2021学年高二上学期期中数学试题(已下线)卷06 直线与圆的方程-单元检测(难)(原卷版)-2021-2022学年高二数学单元卷模拟(易中难)(2019人教A版选择性必修第一册+第二册)(已下线)专题20 《圆与方程》中的周长与面积问题(1)-2021-2022学年高二数学同步培优训练系列(苏教版2019选择性必修第一册)(已下线)专题05 《圆与方程》中的压轴题(1)-2021-2022学年高二数学同步培优训练系列(苏教版2019选择性必修第一册)
8 . 在①
,②
的面积为
,这两个条件中任选一个,补充在下面问题中,并解决该问题:
在
中,角
,
,
所对各边分别为
,
,
,已知
,______,且
.
(1)求
的周长;
(2)已知数列
为公差不为0的等差数列,数列
为等比数列,
,且
,
,
.若数列
的前
项和为
,且
,
,
.证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0009025adccede76783a0a4d95cb4f13.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adbd3e8cf8325999cde03adf845d3dd0.png)
在
![](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/f135978c10b811cb73a6b13a28c0c509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a3c442579603164f3fc19458677d307.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
(2)已知数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae345071d486de6c861346b2ebe02564.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3aaee408bdec05bbdfcd4b841a331e61.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5c340fdadffa2f9120a70430ce477f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46d12bacf6421a87f6f671dac42aa482.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0617cd8b7770e1ce00b053c21b207f85.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4d5a182ffa9c09559c26a5ec90b1f3a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0704f453b2de48d36911f7db496bbf82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d12240edb7736011f3be4964220094e.png)
您最近一年使用:0次
解题方法
9 . 在①
;②
;③
三个条件中任选一个,补充在下面问题中,若问题中的三角形式等边三角形,给出证明;若问题中的三角形不是等边三角形,说明理由
问题:是否存在等边
,它的内角
,
,
的对边分别为
,
,
,满足:
, .
注:如果选择多个分别解答,按第一解答给分
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73565f0c1c6d8d0c64904456f39f475d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb084c14264b0f6ddcaf513b062dd459.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9188224bc7da1a37189afbe1cb042e5.png)
问题:是否存在等边
![](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/3a64b4d679a2a1364ef822f2f0d04960.png)
注:如果选择多个分别解答,按第一解答给分
您最近一年使用:0次
2020-12-14更新
|
363次组卷
|
2卷引用:福建省泉州市第九中学2023届高三下学期第一次月考数学试题
10 . 在
中,
,
,
在
上,且满足
.
(1)求证:
为
的中点;
(2)若
,求
的面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16e0c5cb53fd85b7a23f0580df6bb49a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d70dc2c20619a4fc12a0cfda59af5b69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b840d291aa9e8d272c1b865cbd2305cc.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d65ed8e87249d3c5b9f30a89f5ded4a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
您最近一年使用:0次
2020-06-29更新
|
176次组卷
|
2卷引用:福建省2020届高三毕业班质量检查测试(B卷)数学(文)试题