(1)设
为虚数单位,求
的实部;
(2)计算:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c05b9832b09731a574d4a4adf7448de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f18abfd9441f24a5fbd1b7e7d5cd1aab.png)
(2)计算:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e71d0503b3feda569aeeb1036876d9c.png)
更新时间:2021-01-26 16:24:26
|
相似题推荐
【推荐1】基本不等式:对于2个正数
,它们的算术平均数不小于它们的几何平均数,即
,当且仅当
时,等号成立.可以推广到一般的情形:对于
个正数
,它们的算术平均数不小于它们的几何平均数,
.当且仅当
时,等号成立.若无穷正项数列
同时满足下列两个性质:①
;②
为单调数列,则称数列
具有性质
.
(1)若
;求数列
的最小项;
(2)若数列
的前
项和为
,判断数列
是否具有性质
,并说明理由;
(3)若
,求证:数列
具有性质
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0158862238e250d2a2598b7d4ecd148.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/140564fb2e11f8411e353d2fa73fbee9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58b2fb1017d5dfe3a300de3e14a71b6f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9304e71a623c4412188a800046a970d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9efff8ec14cb242e793afab4468bf2e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a2617515e5ce81b3f5d9f4e806b21b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6879960be91ea52297d587e9a014f54a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/17fac66473a039bdb47c2a248b0f4854.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
(2)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f329b217e1051b23f0d61023cdc6e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b9bb1963d176a00c82828c93ca0e2c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d013861990cf331c82eb453416ae31bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4247739746b8ddf1403541047e8b5580.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5ab0309e2cd35585ea9fb2cc3017abf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
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解答题-证明题
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(0.4)
名校
【推荐2】已知数列
的首项为1,记![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2711dcec2b499c0a8a7481fe0a301ef6.png)
.
(1)若数列
是公比为3的等比数列,求
的值;
(2)若数列
是公差为2的等差数列,①求证:
;②求证:
是关于
的一次多项式.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2711dcec2b499c0a8a7481fe0a301ef6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec0637a42313e1914a6fb1cadf1afda4.png)
(1)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/934d2775b6bd0885b697afb4209993fa.png)
(2)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2fc1d897837062f069747d9de5c88f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24a95cb9161333c191b3e33d76139ee7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
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(0.4)
真题
名校
【推荐1】已知数列
,从中选取第
项、第
项、…、第
项
,若
,则称新数列
为
的长度为
的递增子列.规定:数列
的任意一项都是
的长度为1的递增子列.
(Ⅰ)写出数列1,8,3,7,5,6,9的一个长度为4的递增子列;
(Ⅱ)已知数列
的长度为
的递增子列的末项的最小值为
,长度为
的递增子列的末项的最小值为
.若
,求证:
;
(Ⅲ)设无穷数列
的各项均为正整数,且任意两项均不相等.若
的长度为
的递增子列末项的最小值为
,且长度为
末项为
的递增子列恰有
个
,求数列
的通项公式.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df5f59bc23cf55f56312c9ed9806371f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d6af9e7b1c23db5584ad8521d4444d5d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/608d034715f9b1dfb306f9c89d383582.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f312c01c634db99e3be2e040681c1e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/62aa8180718d9578d089bebd4b1acf60.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(Ⅰ)写出数列1,8,3,7,5,6,9的一个长度为4的递增子列;
(Ⅱ)已知数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a639de56413ec51b25f72be898f31cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8204e935be0688ce1561d9107b635480.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4610754dff007c541aa4887d8705329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/477bb738134dc0d32a331ac5c634574b.png)
(Ⅲ)设无穷数列
![](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/c5873c01192b7d33b7483f444f90b5b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ed47813750761cc4d776edc2fbe2240.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5873c01192b7d33b7483f444f90b5b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ed47813750761cc4d776edc2fbe2240.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b762a12ba0a9890640d9e471e0597467.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/500063042d9f5375f664a8963f80a315.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
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解答题-问答题
|
较难
(0.4)
【推荐2】已知数列
满足:
,
,其中
,数列
满足:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b89dee6581c20e3a45ae3ad664cfc4d.png)
(1)当
时,求
的值;
(2)证明:
对任意
均成立,并求数列
的通项公式;
(3)是否存在正数
,使得数列
的每一项均为整数,如果不存在,说明理由,如果存在,求出所有的
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88285bcde29db874f4618af9cae56939.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f56a87b3ba4663d6cae22f9fe851dc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f0d68648b10fce54dfc19c5ee60086d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fce83115a50f99e08e9a2db7267aeed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b89dee6581c20e3a45ae3ad664cfc4d.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5095a28bb1b91bf6bed9e2cfbd76bb18.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8cf8ae8e4583f0c2c15f2b34b7078bf2.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f9beb741b90ae065614bb68ba60dbca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36b98ef143f8159f3a7dafa1fd2f2370.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fce83115a50f99e08e9a2db7267aeed.png)
(3)是否存在正数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
您最近一年使用:0次