解题方法
1 . 如果n项有穷数列
满足
,
,…,
,即
,则称有穷数列
为“对称数列”.
(1)设数列
是项数为7的“对称数列”,其中
成等差数列,且
,依次写出数列
的每一项;
(2)设数列
是项数为
(
且
)的“对称数列”,且满足
,记
为数列
的前
项和.
①若
,
,…,
构成单调递增数列,且
.当
为何值时,
取得最大值?
②若
,且
,求
的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd94aeeecf0123921d4aef51c5defcf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/341bd4ff68347b38c8e3f9e5a3b665dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/692f0652866d5e18fa597d40bfc3cac2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7104e10aa92b7fd3eb4e497263186664.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(1)设数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a447e5baee4f7518706498d4aca7553b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57a03258158539436dd0e35c7e50e771.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)设数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/897d8f6cf00391f1b3ff70432f0121b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b08c58baacec3cd0c0a06e267fa9ec5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c972cbd63decec197aec1bdc306de67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a22e9369b6a9bb29239a519c10ec392c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
①若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7936359df4c926b72b48c6fdae55f12d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b76f79be89b8c6227b68eded6b675546.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9e5dfcc28321b563a8012ec2899c502.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db0e83ab6e88006fcca1d1b92e474d38.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a31ec8dee46f3affe69cbdb2abbe8feb.png)
②若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebea127cabddcc7adf4fe527b2472e5b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f5369a97c0c1c45293ac014bd060d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
您最近一年使用:0次
2 . 差分法的定义:若数列
的前
项和为
,且
,则
时,
.例如:已知数列
的通项公式是
,前
项和为
,因为
,所以
.
(1)若数列
的通项公式是
,求
的前
项和
;
(2)若
,且数列
的前
项和分别为
,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.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/314fa1f4da470780673cc7246974180c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0704f453b2de48d36911f7db496bbf82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9361afc7cc02253140585eedc39a695d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/677e46ecd051c92489c0d1d458932f37.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/e3bd2e55bb083a90ecba8cc98fac9536.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/237ce153a42d4e2378d5435051734cb3.png)
(1)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8bd845d1bfac72200926447db04563fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77af844c4444e536adae9bc0b1cff614.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c04f062dc12653209868713f2142fe06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee1c51f15c934050099b460b19a04f4b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/038e3af7c9f2fb642b9209415662aeff.png)
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2024-05-30更新
|
168次组卷
|
2卷引用:黑龙江省伊春市铁力市第一中学校2023-2024学年高二下学期期中考试数学试卷
名校
解题方法
3 . 意大利著名数学家斐波那契在研究兔子繁殖问题时,发现有这样的一列数:
,该数列的特点是:从第三个数起,每一个数都等于它前面两个数的和,人们把这样的一列数所组成的数列
称为“斐波那契数列”,则
是斐波那契数列中的第______ 项.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a638fcc8e7d8283654e836b24b938d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa371b6d8ee9bd048308878e0b4ea14c.png)
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名校
解题方法
4 . 若给定数列
,对于任意的
,若满足
,则称
为“
型数列”.若数列
满足:
,
,当
时,
.
(1)判断数列
是否为“
型数列”,并证明;
(2)求数列
的通项公式;
(3)若
,
,使不等式
成立,求实数
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e97769855336d73371930df1f187875e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b44c9c095c6817ad1908118a8fe5a4b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f54ea75eebaf67b500b8f80f050f1e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2693734765399876e9e93cdb110231c4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0704f453b2de48d36911f7db496bbf82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cbf7a076d6cfbbabf8d9ac6f814add7.png)
(1)判断数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13a8c42bbeebd847037ea509702132bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f54ea75eebaf67b500b8f80f050f1e6.png)
(2)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/878b4bc8b23c9f486874016f32221333.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7a67d9c9d7a6771dd2d3578cd4ab05c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd4741ab55cc092588667a7a1397fc2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
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名校
解题方法
5 . 已知数列
的前n项和为
.若对每一个
,有且仅有一个
,使得
,则称
为“X数列”.记
,
,称数列
为
的“余项数列”.
(1)若
的前四项依次为0,1,
,1,试判断
是否为“X数列”,并说明理由;
(2)若
,证明
为“X数列”,并求它的“余项数列”的通项公式;
(3)已知正项数列
为“X数列”,且
的“余项数列”为等差数列,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f093c61867ee4ce75f951d46b9b123.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f6b18b109a656b62fb173680ae99ca7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a42dd37c118e64c46c7fc37e21081745.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/450706c32e58d9e6ad2f14aabf9e81ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f093c61867ee4ce75f951d46b9b123.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acbc6a613224461ade69362d46550474.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d255ea8e125b603d6b640bdf4a804922.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(3)已知正项数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/771ca8c38c8a1646c83481a1d2bcfdfa.png)
您最近一年使用:0次
2024-05-07更新
|
1479次组卷
|
4卷引用:黑龙江省牡丹江市第三高级中学2024届高三下学期第四次模拟数学试卷
黑龙江省牡丹江市第三高级中学2024届高三下学期第四次模拟数学试卷江苏省南京市2024届高三第二次模拟考试数学试题(已下线)专题14 学科素养与综合问题(解答题19)湖北省襄阳市第五中学2024届高三下学期第四次适应性测试数学试题
6 . 在一个数列中,如果
,都有
(
为常数),那么这个数列叫做等积数列,
叫做这个数列的公积.已知数列
是等积数列,且
,公积为8,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d12d0bd9afdd4e53ff37f5bfcaa1106c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b14871c171d5a7cb171534631e6a6ce8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cefeddf71dca8ae824328df3f0e5e1e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9b21a347b87e55b31b16e23bdcc4f15.png)
A.28 | B.20 |
C.24 | D.10 |
您最近一年使用:0次
名校
解题方法
7 . 定义
为
个正数
的“均倒数”,若已知数列
的前
项的“均倒数”为
,又
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ed7720846d6a7b71965ee5e1e347513.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d265ce22f599d3c8fd71724de8f28fa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0549186c87ed4463421b8bcfae7c475e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac9f0acefd534c6c1f18b3a0b6983c46.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/027d2b0a3097cb4fd649e330dcba6a23.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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2024-04-29更新
|
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黑龙江省大庆市大庆中学2023-2024学年高二下学期5月期中考试数学试题重庆市第八中学2023-2024学年高二下学期期中考试数学试题(已下线)模块三 专题3 高考新题型专练(专题2:新定义专练)(北师大)(高二)
8 . 已知数列
的各项均为正整数,设集合
,
,记
的元素个数为
.
(1)若数列A:1,3,5,7,求集合
,并写出
的值;
(2)若
是递减数列,求证:“
”的充要条件是“
为等差数列”;
(3)已知数列
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7f885247785940c5c849210fb6f8abc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4884c506476f191d7919cd266c8c0212.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/47a0c2bb484bf523189b093485eca999.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b68df477b3ee45ac0f725db00d465a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c1ff5cb5a9d88ed7db2c06683c3e355.png)
(1)若数列A:1,3,5,7,求集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b68df477b3ee45ac0f725db00d465a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c1ff5cb5a9d88ed7db2c06683c3e355.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3197c615558fee3993d2a8deb9091f0a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
(3)已知数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5d509697c5391a7c24d9bbc2c82422b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ff241fc46c23ac975c5b39e87a9e46a.png)
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2024-04-19更新
|
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4卷引用:黑龙江省双鸭山市友谊县高级中学2024届高三下学期高考模拟(一)数学试题
黑龙江省双鸭山市友谊县高级中学2024届高三下学期高考模拟(一)数学试题吉林省长春市长春吉大附中实验学校2023-2024学年高二下学期5月期中考试数学试卷(已下线)2024年北京高考数学真题平行卷(基础)(已下线)集合与常用逻辑用语-综合测试卷B卷
名校
解题方法
9 . 如果一个数列从第二项起,每一项与它前一项的比都大于3,则称这个数列为“
型数列”.
(1)若数列
满足
,判断
是否为“
型数列”,并说明理由;
(2)已知正项数列
为“
型数列”,
,数列
满足
,
,
是等比数列,公比为正整数,且不是“
型数列”,求数列
的通项公式.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4c783bab7586f60dc14d4f10b6d5b12.png)
(1)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8f0b434ccd94f4badb2ab572b7ba012.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4c783bab7586f60dc14d4f10b6d5b12.png)
(2)已知正项数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4c783bab7586f60dc14d4f10b6d5b12.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eaa4921de71ae60a9ba615904a419136.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af5cf9c12181dd8683944b2b30bf8e08.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4c783bab7586f60dc14d4f10b6d5b12.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
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名校
解题方法
10 . 数列
满足:
是等比数列,
,且
.
(1)求
;
(2)求集合
中所有元素的和;
(3)对数列
,若存在互不相等的正整数
,使得
也是数列
中的项,则称数列
是“和稳定数列”.试分别判断数列
是否是“和稳定数列”.若是,求出所有
的值;若不是,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62e567d7e9761951a266953c8d5042ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e4b7a84d1c2089430f5adbf0f52731e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2788ae6bae8e954fb96b9a3393adc19.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a55e03428497ac0ea2aa80fe5bdcd939.png)
(2)求集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5bb0582b0e415def42abf1d0a567dccb.png)
(3)对数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f04755f109e1dc24e89113809280ece.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/932441c3185a1e55e2dfda8ba7f1e419.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62e567d7e9761951a266953c8d5042ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7600d2cfbdc6146db96cc545706004f6.png)
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2024-03-22更新
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5卷引用:黑龙江省双鸭山市第一中学2023-2024学年高二下学期4月月考数学试题
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