1 . 已知等比数列
的各项均为负数,记其前
项和为
,若
,则
( )
![](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/dae8ee81591ef51f4be12f6871804edc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af9bbe98100c8067ff36ac536d043a85.png)
A.-8 | B.-16 | C.-32 | D.-48 |
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2 . 在①
,
,
,
成等比数列,②
,
,③
,
,这三个条件中任选一个,补充到下面的问题中并作答.
问题:已知数列
是公差为正数的等差数列,______.
(1)求数列
的通项公式;
(2)数列
的前
项和为
,对任意的
有
恒成立,求
的取值范围.
注:如果选择多个条件分别解答,按第一个解答计分.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c1ccc6c74b8754e9bcbb3f39a11b6f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc858b7a95c5006a44067022da09f667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b8622956cdfdf378d6d25ae414176a1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b004c6e19326ef2fb8567c3f6b2ddf7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31cfb6d7ca3120ee0ebadacb5f23c8e2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9564f4b9ad9898c7648eb55efa0ffa19.png)
问题:已知数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25cbe66fe4e84b4022721122baab4a3.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/ccb3185977be193745f403547d1e9800.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7eaeb8d726023f0ea11e9bb426a82dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
注:如果选择多个条件分别解答,按第一个解答计分.
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解题方法
3 . 已知椭圆
的离心率为
其左右焦点分别为
下顶点为A,右顶点为B,
的面积为 ![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acac46663213391d6b2615cecda7e48c.png)
(1)求椭圆 C 的方程;
(2)设不过原点O 的直线交C于M、N两点,且直线
的斜率依次成等比数列,求
面积的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a869ea8dd6c0388b88436a856ebad3a9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ba447f2abb9bd37cc8d3f607f7e694a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1689df51a5cf26cec30ad609ddfefb9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3c07ebcbfacda073208d483c58e8a84.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acac46663213391d6b2615cecda7e48c.png)
(1)求椭圆 C 的方程;
(2)设不过原点O 的直线交C于M、N两点,且直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d81e42001b5d929e325fa0c801b7242c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4f02028a3847c4807c2d3cf0ea7efb8.png)
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|
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3卷引用:陕西师范大学附属中学2024届高三下学期第十次模考数学(理)试卷
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解题方法
4 . 已知在正项数列
中,
,且
成等差数列.
(1)求数列
的通项公式;
(2)若数列
满足
,求数列
的前
项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e0837d627cf104e2895704e08053ecb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e5e62c0047941b1f0ef849c411a5f54.png)
(1)求数列
![](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/8f769fa13fd117b18b70c7e606a6a522.png)
![](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/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
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解题方法
5 . 记
的内角A,B,C的对边分别为a,b,c,且a,b,c成等比数列,以边
为直径的圆的面积为
,若
的面积不小于
,则
的形状为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1a9c6a736e6eac98a676fa3232db5a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd4ece8552b387eb20f633c32f8142f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41322821ce31416fdac8dd6e0aa41c71.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
A.等腰非等边三角形 | B.直角三角形 | C.等腰直角三角形 | D.等边三角形 |
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解题方法
6 . 已知等差数列
的公差为
,且
是
与
的等比中项,则数列
的前
项和为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274a9dc37509f01c2606fb3086a46f4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7fd71bc7e6668f90f259ad0b06dd60c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c1ccc6c74b8754e9bcbb3f39a11b6f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc858b7a95c5006a44067022da09f667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b7f27ebcef70a3ebbbe8d2e53ea0896.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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解题方法
7 . 在
中,角
所对的边
成等比数列,角
是
与
的等差中项.
(1)若
,求
的面积;
(2)求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f13a05f5aca98574bb1f927123490de4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03837b3769eda7f0d3804cc5ad4a6d60.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/367de5eb4da2eb016a6bfc78e25f4ceb.png)
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解题方法
8 . 已知数列
满足
,若
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dbd9ff686703cad03aa383e5fec21.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e6cbbec0f900da8864d00e396893c98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ea8d0e50065114b05ef2dc1ea1129cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb334e165679c6cb500c994cffa47147.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dbd9ff686703cad03aa383e5fec21.png)
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9 . 已知数列
满足
,若
,
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e6cbbec0f900da8864d00e396893c98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f966272f7781790ff27e40db6b525253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e0f78ff79e35f9b7d63a4e9add024a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dbd9ff686703cad03aa383e5fec21.png)
A.![]() | B.![]() | C.3 | D.5 |
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名校
解题方法
10 . 记
是公差为整数的等差数列
的前n项和,
,且
,
,
成等比数列.
(1)求
和
;
(2)若
,求数列
的前20项和
.
![](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/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ceda82fbc56d664a5d8b8c9e8de1fd18.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c50577e4ada1da0aa7abb890dcf3026.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8fdf21434449236f1d5435bed6bc5e09.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e7f2c7f7886b4c988397c9697225c20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2f710b0e6ccca316852bf3a94f68135.png)
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|
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