1 . 差分法的定义:若数列
的前
项和为
,且
,则
时,
.例如:已知数列
的通项公式是
,前
项和为
,因为
,所以
.
(1)若数列
的通项公式是
,求
的前
项和
;
(2)若
,且数列
的前
项和分别为
,证明:
.
![](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/314fa1f4da470780673cc7246974180c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0704f453b2de48d36911f7db496bbf82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9361afc7cc02253140585eedc39a695d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/677e46ecd051c92489c0d1d458932f37.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/e3bd2e55bb083a90ecba8cc98fac9536.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/237ce153a42d4e2378d5435051734cb3.png)
(1)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8bd845d1bfac72200926447db04563fc.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/08eb71ecf8d733b6932f4680874dbbf3.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77af844c4444e536adae9bc0b1cff614.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c04f062dc12653209868713f2142fe06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee1c51f15c934050099b460b19a04f4b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/038e3af7c9f2fb642b9209415662aeff.png)
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2卷引用:黑龙江省伊春市铁力市第一中学校2023-2024学年高二下学期期中考试数学试卷
2 . 已知
,
,平面内动点P满足
.
(1)求动点P的轨迹C的方程;
(2)动直线
交C于A、B两点,O为坐标原点,直线
和
的倾斜角分别为
和
,若
,求证直线
过定点,并求出该定点坐标;
(3)设(2)中定点为Q,记
与
的面积分别为
和
,求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48d195911a91d12edd5685f6cd963fa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/743eac5ef7cd9452d9678d797da748ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0cb18941b1e55e62e6c3f54a35ccb214.png)
(1)求动点P的轨迹C的方程;
(2)动直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b90e0f35eda1a729fed485f83da5ea9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b5858ee1ce52b251816757257a11c29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46f478abeeb4da23121b652cf907972d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
(3)设(2)中定点为Q,记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/592f84fbbd939b954f52dc6b8c009b53.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a51aab5c5e99207337fb64603887579c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e097c8d4c948de063796bd19f85b3a9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e0bd63f55069a3bc870915010b39225.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/884d40a97fd767e95f34f3b91ab8d84c.png)
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3 . 正三棱柱
内切球(球与上下底面和侧面都相切)的半径是
为棱
上一点,若二面角
为
,则平面
截内切球所得截面面积为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a266ae7eacf6133d6e6dcc7c7eeb7f8d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/325fbf7c39864c58789bc8ebe853dbe9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ac09dc1ca2cdd7aef28c218763d3e4d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/500df0e782bb081e608f4bc1d576afcf.png)
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解题方法
4 . (1)若
,
,求
的取值范围;
(2)证明:
;
(3)估计
的值(保留小数点后3位).
已知
,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fad1dd76d5b72f10f5bb62693a2996f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19c37e166515544d73dfcf03cdc084d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d3a73ba5ea3b9218649d350387a3f83.png)
(3)估计
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e24d42f61784c642e9eb1316afdd2ad.png)
已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/695450724faafa68f7acabe8a3b504b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d230beb82a9f553b1e3e7cc7cd15d7f1.png)
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5 . 如图抛物线
,过
有两条直线
与抛物线交于
与抛物线交于
,
斜率为1,求
;
(2)是否存在抛物线
上定点
,使得
,若存在,求出
点坐标并证明,若不存在,请说明理由;
(3)直线
与直线
相交于
两点,证明:
为
中点.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/159a2d4945049c5a8f525f18763eba91.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52b385adf402cd17bddace02fdb32030.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/254d90ef7eba319615e1fd6e01f6abd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c11bcc7389ee99011b2d77ee0bb4018.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91e1e4115d78e625e9e0f47cdade3286.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e9b0f5f44abbc6544a2f672b025b013.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2401bc9c26cc3b0b8384c7139bd58fff.png)
(2)是否存在抛物线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63b0b8816e5284e07f4377c88fa7980e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
(3)直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d585d2d6643471640905d234d9538c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6b0a3fa475b24f57ecd79c681259561.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6bce3d91ca23b86d8c6625f2632e437.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
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6 . 下列说法正确的是( )
A.数据的频率分布直方图的纵坐标为频率 |
B.已知样本数据![]() ![]() ![]() |
C.若![]() ![]() ![]() |
D.已知![]() ![]() ![]() ![]() |
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7 . 在高二选科前,高一某班班主任对该班同学的选科意向进行了调查统计,根据统计数据发现:选物理的同学占全班同学的80%,同时选物理和化学的同学占全班同学的60%,且该班同学选物理和选化学相互独立.现从该班级中随机抽取一名同学,则该同学既不选物理也不选化学的概率为( )
A.0.125 | B.0.1 | C.0.075 | D.0.05 |
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2卷引用:黑龙江省大庆外国语学校2023-2024学年高二下学期第二次教学质量检测数学试卷
8 . 一个圆锥的侧面展开图是圆心角为
,面积为
的扇形,则下列论断正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0211da37e92f915e781691296578ba0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cf1f865bafd4a820406d336d99f8091.png)
A.圆锥的母线与底面所成角的正弦值为![]() |
B.圆锥内部有一个圆柱,并使圆柱的一个底面落在圆锥的底面内,当圆柱的体积最大时,圆柱的高为![]() |
C.圆锥内部有一个球,当球的半径最大时,球的内接正四面体的棱长为![]() |
D.圆锥内部有一个正方体![]() ![]() ![]() ![]() ![]() |
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解题方法
9 . 已知数列
的前n项和为
.若对每一个
,有且仅有一个
,使得
,则称
为“X数列”.记
,
,称数列
为
的“余项数列”.
(1)若
的前四项依次为0,1,
,1,试判断
是否为“X数列”,并说明理由;
(2)若
,证明
为“X数列”,并求它的“余项数列”的通项公式;
(3)已知正项数列
为“X数列”,且
的“余项数列”为等差数列,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f093c61867ee4ce75f951d46b9b123.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f6b18b109a656b62fb173680ae99ca7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a42dd37c118e64c46c7fc37e21081745.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/450706c32e58d9e6ad2f14aabf9e81ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f093c61867ee4ce75f951d46b9b123.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acbc6a613224461ade69362d46550474.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d255ea8e125b603d6b640bdf4a804922.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(3)已知正项数列
![](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/771ca8c38c8a1646c83481a1d2bcfdfa.png)
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4卷引用:黑龙江省牡丹江市第三高级中学2024届高三下学期第四次模拟数学试卷
黑龙江省牡丹江市第三高级中学2024届高三下学期第四次模拟数学试卷江苏省南京市2024届高三第二次模拟考试数学试题(已下线)专题14 学科素养与综合问题(解答题19)湖北省襄阳市第五中学2024届高三下学期第四次适应性测试数学试题
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10 . 在
中,
,再从下列四个条件中选出两个条件,①
;②
;③
;④面积为
;使得
存在且唯一,则这两个条件是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2449982298e35e2f1bf9082d1f5edf62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c049333c882fdfc23cbcae98a5daea63.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6de1d395e6c48c0676a1488a299479d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ceba46526c1a7df5929c00cd257dba3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/718358dfd51863e2db379726913fb352.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
A.①② | B.①③ | C.②③ | D.①④ |
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