解题方法
1 . 若数列
,
满足
,则称数列
是数列
的“偏差数列”.
(1)若常数列
是数列
的“偏差数列”,试判断数列
是否一定为等差数列,并说明理由;
(2)若无穷数列
是各项均为正整数的等比数列,且
,数列
为数列
的“偏差数列”,数列
为递减数列,求数列
的通项公式;
(3)设
,数列
为数列
的“偏差数列”,
、
且
,若
,(
)对任意的
恒成立,求
的最小值.
![](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/6f1ba05858ddb902eda106c0361b2e89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(1)若常数列
![](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/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)若无穷数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ea11bd18577ee314988bc70b0caf23f.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/3b3b8eff9000900bf5b26afd3489cb3b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(3)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4523dca11f510fac3a51d406fd78448.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/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af4a2ab6d0957e52a1242e6d899be539.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d1512b9a0d9d79f8b71ced14eacd85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/658f7e866c7ae90f7c0d1444000d7a4b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa72c594ebe33496fa7b9edf1db5c7e1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c5dd1562138ab60802c33a17a8d7867.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5db3536b4f6b80285e2044bec5ab20bd.png)
您最近一年使用:0次
2 . 数列
中,
,
,数列
是首项为4,公比为
的等比数列,设数列
的前
项积为
,数列
的前
项积为
,
的最大值为( )
![](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/53271336649378a043f9da8b8bdc1cfc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.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/fcc31dcdb99754fc452ff2b92a2fb8c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66d4e8502106802f1485c3b0f28f2664.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7140a6dbc512a0af4f3d8cea633e0d8c.png)
A.4 | B.20 | C.25 | D.100 |
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3 . 已知数列
中,
,
,
,若对任意的正整数
及
,不等式
总成立,则实数
的取值范围为______ .
![](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/482a465ab85a8fa0ceb42eca5c7a65c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e145b6046bc80d0ffecc61ac67c87ca1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9563c44af5c0eb9ced0959f2d5921c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d366f67f45812281fb8817fa53bdaa1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
您最近一年使用:0次