已知正项数列
满足
,
.
(1)求数列
的通项公式;
(2)证明:
.
(附:
,
,当且仅当
或
时取等号)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41f6638fc813b8e47d555706a2081433.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86fc336b4a83bf6d66c4afcc431597f8.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a766124d7e5a66cf31d330401bf3b9ce.png)
(附:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65bc68f793cebdd43ba51dd9983b7b21.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fee4e4ef6bc78dc8e69bf99c2807b7b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa448dc518e40c705576ecfcb95eaf7f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c87b351f16728b0023fd63678f8103c7.png)
22-23高二下·江西吉安·期末 查看更多[2]
更新时间:2023-08-01 18:05:05
|
相似题推荐
解答题-证明题
|
较难
(0.4)
【推荐1】已知函数
的定义域为N+,且![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d1d50f8a35319bd0725f8fc5ee14990.png)
(1)求f(3)、f(4)的值;
(2)记
求证:数列
是等比数列;
(3)求(2)中数列
的通项公式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f6bfdb24ecf5da863405c2b40936ff9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d1d50f8a35319bd0725f8fc5ee14990.png)
(1)求f(3)、f(4)的值;
(2)记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0760d26552d695d0797f63ad831b35cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac6d7512f83e15bdcc3b8093470c1b07.png)
(3)求(2)中数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29518f13a1ebc3fff8181c2d7cfba22f.png)
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解答题-应用题
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【推荐2】一计算装置有一数据入口A和运算结果的出口B,将正整数列
中的各数依次输入A口,从B口得到数列
.结果表明:①从A口输入
时,从B口得到
.②当
时,从A口输入
,从B口得到的结果
是将前一结果
先乘以正整数列
中的第
个奇数,再除以正整数列
中的第
个奇数.
(1)从A口输入2和3时,从B口分别得到什么数?
(2)猜测并证明当入口A输入正整数列
时,从B口得到数列
的通项公式.
(3)为了满足计算需要,工程师对装置进行了改造,使B口出来的数据
依次进入
口进行调整,结果为一列数据
.若使
,问非零常数
、
满足什么关系式,才能使
口所得数列
为等差数列?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6728e999bd176ddf3ae69b46bad345fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c87b351f16728b0023fd63678f8103c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/14835bf3f00139ccec0694d0924db795.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0704f453b2de48d36911f7db496bbf82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7230de53663c75658c58bbf206a0085.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6728e999bd176ddf3ae69b46bad345fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96e66fef6fd59fd11929c390d5b12dcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6728e999bd176ddf3ae69b46bad345fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a0876215b2fd463d151523cd3c6b447.png)
(1)从A口输入2和3时,从B口分别得到什么数?
(2)猜测并证明当入口A输入正整数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6728e999bd176ddf3ae69b46bad345fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
(3)为了满足计算需要,工程师对装置进行了改造,使B口出来的数据
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f329b217e1051b23f0d61023cdc6e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3580125ea0a7e3c1edd9053079dbb9e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f329b217e1051b23f0d61023cdc6e69.png)
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解答题-问答题
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(0.4)
名校
解题方法
【推荐1】设正项数列
的前
项和为
,对任意
都有
成立.
(1)求数列
的前
项和
;
(2)记数列
,其前
项和为
.
①若数列
的最小值为
,求实数
的取值范围;
②若数列
中任意的不同两项之和仍是该数列中的一项,则称该数列是“封闭数列”.试问:是否存在这样的“封闭数列”
,使得对任意
,都有
,且
.若存在,求实数
的所有取值;若不存在,请说明理由.
![](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/a37a59558292ad6b3d0978bfd7484990.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71e3fada69fbdbf095b43d1367df81bb.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(2)记数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32140a15a776309b442eb84ca9383ade.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
①若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5eded65284816fdf6bf335b0c2a78e6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9b647ac8a8174071a4f332a00b5507b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
②若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fce83115a50f99e08e9a2db7267aeed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fce83115a50f99e08e9a2db7267aeed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a37a59558292ad6b3d0978bfd7484990.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/113991390704e023f257ae0940f17765.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8569da8611abcc62075e1e1141def469.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
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名校
【推荐2】已知数列
为等差数列,公差为d,前n项和为![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34a60fab9ac1eb590b1e3a9b1567f570.png)
(1)若
,求
的值;
(2)若![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6906cb4d4ef83ad429f310c9f34c5eb1.png)
中恰有6项在区间
内,求d的取值范围;
(3)若
,集合
,问能否在集合A中抽取到无穷多个不全相等的元素组成一个新数列
,使得此新数列
满足从第二项开始,每一项都等于它的前一项和后一项的调和平均数.若能,请举例说明;若不能,请说明理由.(注:数
叫做数a和数b的调和平均数).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34a60fab9ac1eb590b1e3a9b1567f570.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0c2d1a12d12803534db0e52cb194489.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08c9965a04c2a6de04e949a15762f372.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6906cb4d4ef83ad429f310c9f34c5eb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/faee44c629af484525bec237764ec0aa.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f8f0b01cb7ad47eced93d118ac2cfc3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77751aae6c35ce2c1b7966887063d46d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fce83115a50f99e08e9a2db7267aeed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fce83115a50f99e08e9a2db7267aeed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eafd0e253a0a62512d50c656de3dc2e9.png)
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解答题-问答题
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较难
(0.4)
名校
解题方法
【推荐1】已知等差数列
和等比数列
,其中
的公差不为0.设
是数列
的前n项和.若
,
,
是数列
的前3项,且
.
(1)求数列
和
的通项公式;
(2)若数列
为等差数列,求实数t;
(3)构造数列
,
,
,
,
,
,
,
,
,…,
,
,
,…,
,….若该数列前n项和
,求n的值.
![](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/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f65fc200f10b97588a0c9896277c9c64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2cb4485663835fc40a9cf82f491d5b3.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a5aa26579e2b5a06008f29096400287.png)
(3)构造数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b715e7842b95f654f16056a7c7f2abe9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b715e7842b95f654f16056a7c7f2abe9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13423c094861baf4b759b7f3d8c3c226.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c1ccc6c74b8754e9bcbb3f39a11b6f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b715e7842b95f654f16056a7c7f2abe9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13423c094861baf4b759b7f3d8c3c226.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57483e04fd1840c87ac5325157149877.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f255d0395fba51ca2d44293cca42e0a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b715e7842b95f654f16056a7c7f2abe9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13423c094861baf4b759b7f3d8c3c226.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/233427826eb2233641fc3a9805f6d206.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7c404311a00652a0a145319bcb3fa6a.png)
您最近一年使用:0次
解答题-证明题
|
较难
(0.4)
名校
解题方法
【推荐2】已知数列
中,
是其前
项的和,
,
.
(1)求
,
的值,并证明
是等比数列;
(2)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/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/786e64ed0bc2783f26af9fe91cc0d81f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/924f0afc89e89dca23956cb91576efb9.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/213e22890204937a5dded4436369390f.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8f822b278c959817f91b794f3dce836.png)
您最近一年使用:0次