1 . 在
中,
,
,若D是AB的中点
,则
;若D是AB的一个三等分点
,则
;若D是AB的一个四等分点
,则
.
(1)如图①,若
,用
,
表示
,你能得出什么结论?并加以证明.
(2)如图②,若
,
,AM与BN交于O,过O点的直线l与CA,CB分别交于点P,Q.
①利用(1)的结论,用
,
表示
;
②设
,
,求证:
为定值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e923e4cdcbea6a029f5ba188a59229d6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb95d089784702a0b6d459f18a4e1e72.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0997b1534ce4817fdc86c4b6c75db29d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2634228ecbd45ba775dca73eaf1cc63.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1bdd1229d9e121bc3bdb2339e76f3e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fda838437dab97586710b6220ee74dcd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/075e483c30716072375e7db13e84ad07.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1030db2fcd7b8f3f0eae7eb063fb7cba.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/7/28/1e3da6d3-e471-4d60-901e-c428805cbbdb.png?resizew=379)
(1)如图①,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63b83647557c93d7f7e9ceee524601a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a2f4b1178f68bd147d1a2a6acd04435.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c94075193c11fe43f2396cff5a485054.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc1070a28cb9cb8553c29747d1993b16.png)
(2)如图②,若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee5388f2e85a72e2414928ff69e0fd13.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1cd8790d5f3cc008befd52e46f42001.png)
①利用(1)的结论,用
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a2f4b1178f68bd147d1a2a6acd04435.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c94075193c11fe43f2396cff5a485054.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0260317a23090e4a019f76ae08614f5.png)
②设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c85b08638081ff0c9651e4ca5792669.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e8454ef2c08a243be83057c34de2f0a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b7e12253044b5abff2a56dcd730ced8.png)
您最近一年使用:0次
名校
解题方法
2 . 如图,在四棱锥
中,
,且
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/10/77f0ef14-6bcd-4653-9638-91b27200afd9.png?resizew=226)
(1)若![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
平面
,证明:点
为棱
的中点;
(2)已知二面角
的大小为
,当平面
和平面
的夹角为
时,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0998d16d7bf13acae5bfb9b8de55ca04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4d5ff57f147aa0628fdd47899b5a132.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/10/77f0ef14-6bcd-4653-9638-91b27200afd9.png?resizew=226)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/638537c0a30676c73fea76c80e0f8bd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
(2)已知二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f479b251fdb01bae6d16abb7f2d694a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d5bca00fa20e6e80480b9d06d2e52ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f571a1aac46c6d0cf440c0ec2846bf9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6943f158bf2f76abed0c58196dbe0bc5.png)
您最近一年使用:0次
2023-04-10更新
|
471次组卷
|
3卷引用:江西省吉安市2023届高三模拟测试数学(理)(一模)试题
名校
解题方法
3 . 如图,已知四棱锥
的底面
是边长为
的正方形,
,
,
是侧棱
上的动点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/31/2630d461-fffd-4096-a924-8db7eb8c0f5a.png?resizew=207)
(1)若
为
的中点,证明:
平面
;
(2)求证:不论点
在何位置,都有
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d618f2f945043c0fc4b2bb492206d4cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2899e607479d8d1c47d954ae9ebb7144.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/31/2630d461-fffd-4096-a924-8db7eb8c0f5a.png?resizew=207)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/373f735f0f04d11f1951eaef1bb78b6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
(2)求证:不论点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84be64d28b1623e71ad989f37336b1f2.png)
您最近一年使用:0次
4 . 如图,在四棱锥
中,
,
,
,
,
,
.
![](https://img.xkw.com/dksih/QBM/2020/12/28/2624004280983552/2626957238157312/STEM/45b69d99-c060-4e3a-bfc4-7267404dbb7a.png?resizew=307)
(1)求证:平面
平面
.
(2)设点
为
的中点,
为棱
的中点,且
,证明:平面
平面
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b80ee363635d73f601654339028daec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26b4565d304bb00b00acf184ce174e58.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71826134c3080aa75becc655a9089855.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/037b342a682cbd4241855a243da3c016.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68d31600cba2d5256c7e78b6122d6755.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf15f23e8531a3127fa09b9a8dacab6a.png)
![](https://img.xkw.com/dksih/QBM/2020/12/28/2624004280983552/2626957238157312/STEM/45b69d99-c060-4e3a-bfc4-7267404dbb7a.png?resizew=307)
(1)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4aa9084b8fe0fe05c4388d1f835587b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(2)设点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef2d41a810bb2c2b61be30c16b257aad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b711c453131b5420cbade7e0e451b908.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6261790c66cc71ee3898afabad0c09f4.png)
您最近一年使用:0次
2021-01-01更新
|
338次组卷
|
3卷引用:江西省吉安市第一中学2021-2022学年高二上学期开学考试数学(理)试题
名校
5 . 完成下列证明:
(Ⅰ)求证:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5de8eb289fde19705d3ebf005cc36e8.png)
;
(Ⅱ)若
,求证:
.
(Ⅰ)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5de8eb289fde19705d3ebf005cc36e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3de4ddc6ed5fc0f34fe195115a391ca4.png)
(Ⅱ)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a2f4630b66f80a5f2b7f186e49b321e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da586544943f6fb62344a58f9e645f70.png)
您最近一年使用:0次
2019-09-12更新
|
1116次组卷
|
3卷引用:江西省吉安市2018-2019学年高二下学期期末教学质量检测数学(文)试题
6 . 如图所示,四棱锥
的底面是边长为1的正方形,侧棱
底面
,且
,
是侧棱
上的动点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/6/86e5f5dd-6996-4e35-91f7-aa55bb982633.png?resizew=170)
(1)求四棱锥
的体积;
(2)如果
是
的中点,求证:
平面
;
(3)不论点
在侧棱
的任何位置,是否都有
?证明你的结论.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8fd3eb538f36e6e722e4ce125266b99b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/6/86e5f5dd-6996-4e35-91f7-aa55bb982633.png?resizew=170)
(1)求四棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
(2)如果
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef6d1ac6e00b74a1218fec878b15cf54.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
(3)不论点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/509d8dd6031dc0ef92075877e53fe201.png)
您最近一年使用:0次
2019-12-12更新
|
154次组卷
|
2卷引用:江西省吉安市(吉安县三中、泰和二中、安福二中、井大附中 )2021-2022学年高二上学期期中考试数学(理)试题
名校
7 . 对于无穷数列
,“若存在
,必有
”,则称数列
具有
性质.
(1)若数列
满足
,判断数列
是否具有
性质?是否具有
性质?
(2)对于无穷数列
,设
,求证:若数列
具有
性质,则
必为有限集;
(3)已知
是各项均为正整数的数列,且
既具有
性质,又具有
性质,是否存在正整数
,
,使得
,
,
,…,
,…成等差数列.若存在,请加以证明;若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3cb1321c970c49c9f6a5635ac23d6a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99699ac8106034f647e4f460b3bf163c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0aa8264eb8eea3025a152318df8720b1.png)
(1)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e836ef3b31693dcaf25b414277e8ae8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d8f894492a8126f5f133dec4cd68833.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c414a10d73f453fc1109e5b2243d2369.png)
(2)对于无穷数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/926b0a2429ebf269f7e9368ac0306956.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15e691589e9aafddefcbb613c7030f89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b68df477b3ee45ac0f725db00d465a1.png)
(3)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bea0dd7e474bcd04db2544427ba0488.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b7470297de40027847c5c73fc5d1719c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7334c46af837676ada9575630a48d60f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0699adb388000a87241d6b113e733cf2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/969293569368540b9517380795cb571b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bfaf6fb5cd9a53f7adc324976735b9a.png)
您最近一年使用:0次
2019-06-18更新
|
1788次组卷
|
5卷引用:江西省吉安市第一中学2024届高三“九省联考”考后适应性测试数学试题(一)
江西省吉安市第一中学2024届高三“九省联考”考后适应性测试数学试题(一)2019年上海市普陀区高三高考三模数学试题广东省湛江市雷州市第二中学2023-2024学年高二下学期开学考试数学试题(已下线)新题型01 新高考新结构二十一大考点汇总-3(已下线)专题06 数列
8 . (1)设
,
,
都是正数,求证:
;
(2)证明:求证
.
![](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/533937a08d1ed87594ac52c658be9649.png)
(2)证明:求证
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14c19d94ff48082c1cd213c82c99abf0.png)
您最近一年使用:0次
2019-06-20更新
|
1180次组卷
|
4卷引用:江西省吉安市五校(安福二中、井大附中、泰和二中、遂川二中、吉安县第三中学)2021-2022学年高二3月联考数学(文)试题
9 . 证明下列不等式.
(1)当
时,求证:
;
(2)设
,
,若
,求证:
.
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d33da711e50e96568facb18cef27165.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acca3abc22da18c01aadf6931e923d4d.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94440d3e4c073f94f2b266ff99d50e74.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67ca5fd57c2c2fcc3c7a574fdd1467d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/feac4de538eecda2cb5cf860cd665261.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c958a97b985acd1662caf320f42904e0.png)
您最近一年使用:0次
2018-07-02更新
|
795次组卷
|
2卷引用:【全国市级联考】江西省吉安市2017-2018学年高二下学期期末考试数学(理)试题
10 . (1)求证:
;
(2)已知函数
,用反证法证明方程
没有负数根.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c04fdf048f747aa8a3790f0100aa1f92.png)
(2)已知函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a6bdcb5a8eaa7b0c2c0dcae47899b6f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86b92b70365c63607daecdc8deb73ecf.png)
您最近一年使用:0次
2018-06-15更新
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478次组卷
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2卷引用:【全国市级联考】江西省泰和县二中、吉安县三中、安福县二中2017-2018学年高二下学期三校联考数学(理)试题