解题方法
1 . 将足够多的一批规格相同、质地均匀的长方体薄铁块叠放于水平桌面上,每个铁块总比其下层铁块向外伸出一定的长度,如下图,那么最上层的铁块最多可向桌缘外伸出多远而不掉下呢?这就是著名的“里拉斜塔”问题.将铁块从上往下依次标记为第1块、第2块、第3块、……、第n块,将前
块铁块视为整体,若这部分的重心在第
块的上方,且全部铁块整体的重心在桌面的上方,整批铁块就保持不倒.设这批铁块的长度均为1,若记第n块比第
块向桌缘外多伸出的部分的最大长度为
,则根据力学原理,可得
,且
为等差数列.
的通项公式;
(2)记数列
的前
项和为
.
①比较
与
的大小;
②对于无穷数列
,如果存在常数
,对任意的正数
,总存在正整数
,使得
,
,则称数列
收敛于
,也称数列
的极限为
,记为
;反之,则称
不收敛.请根据数列收敛的定义判断
是否收敛?并据此回答“里拉斜塔”问题.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c5abd5f2fc2744d7f706656575b7262.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12444d6e8d3b097a9d090e6ed06042e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a0876215b2fd463d151523cd3c6b447.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ee45219629dd30af171588e646f8b12.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b7b78e4a03d4595f14be42054b61dfc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
(2)记数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
①比较
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c6b6c6934eda8f0838d0ba881be2211.png)
②对于无穷数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1fd18a909cecbaee7115d6b15631d83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/711c92626a97e6b778b3aa86e663ee97.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4ccd4537f4dee2050ade38b972eb9b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/74d1d3b9d14068d68a7cff35ce3e872c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f4691ee07234d7cfc8a21bed1236c98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1fd18a909cecbaee7115d6b15631d83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1fd18a909cecbaee7115d6b15631d83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b85738365edd32d8df21b2d36518029.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1fd18a909cecbaee7115d6b15631d83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d013861990cf331c82eb453416ae31bc.png)
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解题方法
2 . 已知函数
.
(1)当
时,求
的极值;
(2)若
恒成立,求实数
的取值范围;
(3)证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8d0dffe17c575a4feb86c28d97182a7.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b108ab31cc093f03cf48ad65429889e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e9c599e8d420006448905acec2b8234.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
(3)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b245ba1efcc5776b03e8669fa30da8aa.png)
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解题方法
3 . 在圆台
中,圆
的半径是2,母线
,圆
是
的外接圆,
,
,则三棱锥体积最大值为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e65ac334119ccd6204402a7aba29a55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f919bd3dde10dbbc076f7ec5149699.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2899e607479d8d1c47d954ae9ebb7144.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c4f6f74444b2b7947fc6e35c8d62322.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84d81d732204a3c2384a27606f858677.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68b40d0d2f3cdd8981bb792ad87efb42.png)
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解题方法
4 . 已知函数
定义域为
,且
,
,则下列结论正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8fd1e808e015f4cb43d2e3a0529ac6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf3ed15aa3dcc4211fb520b5b942c989.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b345aed46b3708d8ec74e54326326aa6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58bdb1299804cdfde51224a32de95405.png)
A.![]() |
B.![]() |
C.若![]() ![]() |
D.若![]() ![]() |
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5 . 若曲线
与
恰有两条公切线,则
的取值范围为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/344ccbf79da6ad7e3709d6fa72efb756.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43500678e0aba349d2cc42f91b5cbe25.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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6 . 已知双曲线
的实轴长为2,离心率为2,右焦点为
,
为
上的一个动点,
(1)若点
在双曲线
右支上,在
轴的负半轴上是否存在定点
.使得
?若存在,求出点
的坐标;若不存在,请说明理由.
(2)过
作圆
的两条切线
,若切线
分别与
相交于另外的两点
、
,证明:
三点共线.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83bf4fd84818abac17a9d21237ac5ce5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(1)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a6b915acceebea47b3fc9e902755557.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
(2)过
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cdcbaa80a48affc347be5a1bb5079a9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50297ad9f7256b4d2efc3462289f18b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50297ad9f7256b4d2efc3462289f18b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4aaf867a11ac4014b51f564478f01f4b.png)
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解题方法
7 . 如图,棱长为2的正方体
中,点
是棱
的中点,则下列结论中正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
A.点![]() ![]() |
B.若![]() ![]() ![]() ![]() ![]() ![]() |
C.三棱锥![]() ![]() |
D.若![]() ![]() ![]() ![]() |
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8 . 若无穷数列
满足:对于
,其中
为常数,则称数列
为
数列.
(1)若一个公比为
的等比数列
为“
数列”,求
的值;
(2)若
是首项为1,公比为3的等比数列,在
与
之间依次插入数列
中的
项构成新数列
,求数列
中前30项的和
.
(3)若一个“
数列"
满足
,设数列
的前
项和为
.是否存在正整数
,使不等式
对一切
都成立?若存在,求出
的值;若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80d6f0757423edb2e5eed9bc8abf85af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
(1)若一个公比为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e976c0663fa749ca749f99842d21ca03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9aa8a716a31b0f51b70fdf9bdb257909.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6399690401e29b0b652dec6448497708.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4741eb4c177d75ca74fe2d36e52ecbc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1cf52946ef832dd2fa7a82dcd6d1bcc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/362832fa3d3c13c1eafd565349d66dce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f4b36b1b5f4d0aff4145e38842edaa6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d16765bfe96c4c2733afdf4099a33f5e.png)
(3)若一个“
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8ae312d758938e1e030a93d78fa9d69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41cf1da18d91f7c98086553d157d1a87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aee956329e95a172d86c86b2f6af7aec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c0c6b2deb3a45dcb0c351566ae84f2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e97769855336d73371930df1f187875e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aee956329e95a172d86c86b2f6af7aec.png)
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9 . 己知椭圆
的左、右顶点分别为
,右焦点为F.动直线l过F且与E相交于A,B两点,定点G使得
.
(2)直线m过点G且垂直于x轴,点P在m上,证明:若
三点共线,则
三点共线:
(3)椭圆E如图所示,请用“尺规作图”的方法在图中作出点F、点G,保留作图痕迹,并写出作图步骤.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8868e2ba4401d727f1bcb1f5483b48f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00442d96d695db2c58bf1fb7165fca94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd5f7f8631964382f4769c8fc020e6f7.png)
(2)直线m过点G且垂直于x轴,点P在m上,证明:若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2956ffa0de0f9d11afe72119b221264a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7489e056192b00dc0973539cf36ab9c.png)
(3)椭圆E如图所示,请用“尺规作图”的方法在图中作出点F、点G,保留作图痕迹,并写出作图步骤.
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10 . 已知函数
有且只有两个零点,则a的范围____________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ee76255706039aa778ff3add3f71a38.png)
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