1 . 在一个有穷数列的每相邻两项之间插入这两项的和,形成新的数列,我们把这样的操作称为该数列的一次“和扩充”.如数列1,2第1次“和扩充”后得到数列1,3,2,第2次“和扩充”后得到数列1,4,3,5,2.设数列a,b,c经过第n次“和扩充”后所得数列的项数记为
,所有项的和记为
.
(1)求
;
(2)若
,求n的最小值;
(3)是否存在实数
,使得数列
为等比数列?若存在,求出
满足的条件;若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf83e20035c3afd6d26ebfd53d768a70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5425108c557f0f21474c045334f97d9c.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dcd08431daac10be93e6fafbc5d4a90.png)
(3)是否存在实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cce224c28ca451c4f105dc3b077736cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
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解题方法
2 . 已知
,
,且
,
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/481e744af0f65e797a35d976c20f2dac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3cd71803df3c72c63ee5fe30661b1a1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d61e2e7cc4834161983649bfac47d872.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f69b1edea06acefd1b2347de4f7721.png)
A.![]() ![]() | B.![]() ![]() | C.![]() | D.![]() |
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3 . 已知函数
,则下列说法正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d39d4e199031b74357e9fbd723916fbc.png)
A.![]() |
B.![]() ![]() |
C.方程![]() ![]() ![]() |
D.若![]() ![]() ![]() ![]() ![]() ![]() ![]() |
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4 . 第二次世界大战期间,了解德军坦克的生产能力对盟军具有非常重要的战略意义.已知德军的每辆坦克上都有一个按生产顺序从1开始的连续编号.假设德军某月生产的坦克总数为N,随机缴获该月生产的n辆(
)坦克的编号为
,
,…,
,记
,即缴获坦克中的最大编号.现考虑用概率统计的方法利用缴获的坦克编号信息估计总数N.
甲同学根据样本均值估计总体均值的思想,用
估计总体的均值,因此
,得
,故可用
作为N的估计.
乙同学对此提出异议,认为这种方法可能出现
的无意义结果.例如,当
,
时,若
,
,
,则
,此时
.
(1)当
,
时,求条件概率
;
(2)为了避免甲同学方法的缺点,乙同学提出直接用M作为N的估计值.当
,
时,求随机变量M的分布列和均值
;
(3)丙同学认为估计值的均值应稳定于实际值,但直观上可以发现
与N存在明确的大小关系,因此乙同学的方法也存在缺陷.请判断
与N的大小关系,并给出证明.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a5e1bb2637455d05313a112c5d745bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/096b1ece1dcd29c59a46a4b3e02cb548.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5031a3a951c4a1d1c5e9f80a5e26513.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93d0f3799612b81e85b87241ec8eee68.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2dcf3400c1490071b390aaac0ad0e102.png)
甲同学根据样本均值估计总体均值的思想,用
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/afb1694f46c040a6c976b2ef3eb3934b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/120e4da3fe22be28b3bb28f28fbcc862.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92da09d5877d3dfe1a856b6353b81906.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b7171e0c9c26b9f39a32d3a61d113cf.png)
乙同学对此提出异议,认为这种方法可能出现
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8a1bd336033c63bc9c4f99ff2b482b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebcc133d5b11b33a904875182d8c8261.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be604061cf1591f7069472269d4c9719.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c50a1cf3b1a6f9a12605cbdf48e5de5c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49bf4a59874878184dadeec74d1781d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53722e8f43d44f9c611398ddaab151f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/afac93e0089a7ffca9a1f720e13b6878.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de3874d2e8c49308151837161d7aa91c.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebcc133d5b11b33a904875182d8c8261.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be604061cf1591f7069472269d4c9719.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b9b7c101f267bbf233da7d3ac30e6f0.png)
(2)为了避免甲同学方法的缺点,乙同学提出直接用M作为N的估计值.当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/270e5f2895909d5b6b6c612a8696565b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fac3649308b528fd56545ba102dc42d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/348388b2590255369527f86fd6be63c3.png)
(3)丙同学认为估计值的均值应稳定于实际值,但直观上可以发现
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/348388b2590255369527f86fd6be63c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/348388b2590255369527f86fd6be63c3.png)
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3卷引用:河南省南阳市社旗县第一高级中学2024届高三下学期三模理科数学试题
5 . 平面直角坐标系
中,动点
满足
,点P的轨迹为C,过点
作直线l,与轨迹C相交于A,B两点.
(1)求轨迹C的方程;
(2)求
面积的取值范围;
(3)若直线l与直线
交于点M,过点M作y轴的垂线,垂足为N,直线NA,NB分别与x轴交于点S,T,证明:
为定值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee31829d0d4d5f779a957d7df8058ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8701e0cce437edc830438b4fe6277d89.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92997b69ceb9cef558c342bb76e9d029.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63309dbc3612815f6dbdee23d9a10adc.png)
(1)求轨迹C的方程;
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3fe95f656b98b53f71a9d72bf0c9a4b9.png)
(3)若直线l与直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b384412acba251d87902ab928902f16.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9abbd1e045367e18c60f74359b479b2.png)
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2卷引用:河南省南阳市社旗县第一高级中学2024届高三下学期三模理科数学试题
6 . 已知抛物线
的焦点为F,过点F的直线l与抛物线交于A、B两点(点A在第一象限),
与
的等差中项为
.抛物线在点A、B处的切线交于点M,过点M且垂直于y轴的直线与y轴交于点N,O为坐标原点,P为抛物线上一点,则下列说法正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8516f71467b419293fa27df70bdaed74.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfe5a58dfdb8f0f9932bd1d2ab40f937.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a83fdf4db29a178d9928fa0893cfff6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
A.![]() | B.![]() ![]() |
C.![]() ![]() | D.![]() |
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2卷引用:河南省南阳市社旗县第一高级中学2024届高三下学期三模理科数学试题
7 . 已知椭圆
的焦距为2,两个焦点与短轴一个顶点构成等边三角形.
(1)求椭圆
的标准方程;
(2)设
,过点
的两条直线
和
分别交椭圆
于点
和点
(
和
.不重合),直线
和
的斜率分别为
和
.若
,判断
是否为定值,若是,求出该值;若否,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad523e69a1bf925e73a22900b9855df2.png)
(1)求椭圆
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9195fe550aabe5aefb626892f4483ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e9b0f5f44abbc6544a2f672b025b013.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f6f17bc385bafb37e8f964e5eb99cd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91e1e4115d78e625e9e0f47cdade3286.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7789a500686c7a73770404ead6af0590.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e9b0f5f44abbc6544a2f672b025b013.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f6f17bc385bafb37e8f964e5eb99cd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e9b0f5f44abbc6544a2f672b025b013.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f6f17bc385bafb37e8f964e5eb99cd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6defc43285a40f7ccb74c1cc04265eba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/423b7ae39db552e60ee8b1d27312306f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/70c6fa2ef2d5a1be4c7c2bd3be4b4366.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b69e3f7ddd51215d00661c09cd900d60.png)
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名校
解题方法
8 . 已知双曲线
的左、右焦点分别为
,根据双曲线的光学性质可知,过双曲线
上任意一点
的切线
平分
.直线
过
交双曲线
的右支于A,B两点,设
的内心分别为
,若
与
的面积之比为
,则双曲线
的离心率为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c29bab2a74ca02d30e0deed068b042f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d2a97987f71835f519b462f5b8f5957.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7775aa57ca0e62216f3039ed88dceed0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bac2f7fe4411d15bdeb4a72e98ea766e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c94fe48bf7af022ecbbe13833fdcc2c8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e9b0f5f44abbc6544a2f672b025b013.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3fb78c5f885034612c0e030b920143d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b1bd8fd746ffacd779249f171d80168.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01e1fcb61ab66a7f514b7bad31d1e2f2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ed517e1f28671f9dac3264ced2720a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e68113ebf789709f8a98d9e5f2f8a31.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eac97e6740365c85ad857aff85cefbe5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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解题方法
9 . 古希腊哲学家发现并证明了只存在5种正多面体,即正四面体、正六面体、正八面体、正十二面体、正二十面体,其中正八面体是由8个等边三角形构成.正八面体在计算机科学中用于三维模型和场景的构建,以及人工智能领域中用于图象识别和处理,另外在晶体和材料科学中也被广泛应用.现有一个棱长为2的正八面体
,如图所示,下列说法中正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73cbd9eb22f75ad5304d8491b314a9a9.png)
A.若点![]() ![]() |
B.若该正八面体的12条棱中点在同一个球的球面上,则该球的表面积为![]() |
C.该正八面体内任意一点到8个侧面的距离之和为定值 |
D.已知正方体![]() ![]() |
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10 . 已知函数
.
(1)设
,讨论函数
的单调性;
(2)若函数
有两个极值点
,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f780c29920993f7646d1f2213a843ce9.png)
(1)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf6a1926b75875ca0c42b8985d6c939e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4669810732b633b60dbeaf0bf57204f6.png)
(2)若函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aca579894dad67bc82cb715fd48e0d70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8c57db4989f590c77347eef49e48e46.png)
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