解题方法
1 . 记
为数列
的前n项和,已知
,且
,
.
(1)求
的通项公式;
(2)设
,
的前n项和为
,求
的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4cf3c9b35c6e0863c581e160ac6a9be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/886df10e12ec98a0529e34cc0b3eb041.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee9388f14f8d7ba3c7f44f1de3672d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f329b217e1051b23f0d61023cdc6e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
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解题方法
2 . 如图,在棱长为2的正方体
中,点E、F、G、H分别为棱
、
、
、
的中点,点M为棱
上动点,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f66fb71b75b63594ebeeeebd1963eed5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/394c5d2f55221975503be8aa18022480.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/23/e2730018-bfe9-46ef-845e-25bb36d3ff0e.png?resizew=160)
A.点E、F、G、H共面 | B.![]() ![]() |
C.点B到平面![]() ![]() | D.![]() |
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解题方法
3 . 在
中,内角A、B、C的对边分别为a、b、c,已知
.
(1)求A的大小:
(2)设
的面积为
,点D在边
上,且
,求
的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10832c901ec403d405954ac327a12f94.png)
(1)求A的大小:
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38387ba1cadfd3dfc4dea4ca9f613cea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d39b6bef27de230acad352f25e954f4e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
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4 . 西秀山白塔位于安顺城南西秀山上,为仿阁楼式六棱九重实心石塔,白塔始建于元泰定三年(公元1326年),初仅为佛用砖塔.清咸丰元年(1851年),这座元代的砖塔倾斜严重,前安顺知府胡林翼倡捐廉银三十两,时值清中叶,我国华南地区开始以“制器尚象”的设计思维尊崇毛笔形状兴建了大批风水塔,以寓当地文风昌盛.位于西秀山的这座古塔正是在这样的潮流下,被设计成了一个套筒式的毛笔状白塔,咸丰二年普定知县邵鸿儒撰《重修安郡文峰碑》记录了这一大盛事,如图,某学习小组为了测量“西秀山白塔”BC的高度,在地面上A点处测得塔顶B点的仰角为
,塔底C点的仰角为
.已知山岭高CD为h,则塔高BC为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b5858ee1ce52b251816757257a11c29.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/23/0332332a-78a0-41cb-81aa-569a3e4521d9.png?resizew=320)
A.![]() | B.![]() | C.![]() | D.![]() |
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5 . 在平面直角坐标系
中,一条光线从点
时出,经直线
反射后,与圆
相切,写出一条反射后光线所在直线的方程______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7795aec93c2c7ac2fd93e6747ca6516c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60d295a4cc3a58f9f38ee98337313c81.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d77f5191798242b7b9b88a75e17e4425.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4e9d81edef2b9140a79084e20b8ba0d.png)
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解题方法
6 . 已知双曲线
,A,B为左右顶点,双曲线
的右焦点F到其渐近线的距离为1,点P为双曲线上异于A,B一点,且
.
(1)求双曲线
的标准方程;
(2)设直线l与
相切,与其渐近线分别相交于M、N两点,求证:
的面积为定值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01a35802f04f793ebd9c8be4c9e21cea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4bcd8ee2d8367c167d6ae0abc741b6b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6dd7ac57d179a9fa8e9fc9a2b0cbf4a1.png)
(1)求双曲线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4bcd8ee2d8367c167d6ae0abc741b6b8.png)
(2)设直线l与
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4bcd8ee2d8367c167d6ae0abc741b6b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25dd698d57d1cf239eb8752aecaaa4f4.png)
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解题方法
7 . 如图,在直三棱柱
中,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/23/a9c3eecb-42f4-4c8a-a953-9f675f010219.png?resizew=143)
(1)求证:
.
(2)若
,
,点E是线段
上一动点,当直线
与平面
所成角正弦值为
时,求点E的位置.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45acdbac251ca6b76a166c1242e71df9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eeed487430a5b8a330f2d0c52166521a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/23/a9c3eecb-42f4-4c8a-a953-9f675f010219.png?resizew=143)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/47af45fbf1714055d9b414a44a8613fa.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4339a40ae9d1947ec3a4b3e2fa3a16cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa7aeb2a8d1437eeb4482c3b6ad9f315.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31dba91f88e6404c86a48df67fdb6d77.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3ffd5c35bba71ea54c28622b6cf505d.png)
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8 . 若集合
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b57d3b34d397317c2b1eca0a4ca9b5a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4b9b470218359a4a47be9244980489e.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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9 . 安顺市第三届运动会于2023年11月8日至11月10日在安顺奥体中心举行.某中学安排4位学生观看足球、篮球、乒乓球三个项目比赛,若一位同学只观看一个项目,三个项目均有学生观看,则不同的安排方案共有( )
A.18种 | B.24种 | C.36种 | D.72种 |
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10 . 已知椭圆
,
,
分别为该椭圆的左,右焦点,以
为直径的圆与椭圆C在第一象限交于点P,则点P的纵坐标为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb4402aeb853b22f20992156957ef0fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5076289823db419f94e9c0c8f4aafd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3fb78c5f885034612c0e030b920143d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/643ef7d761de0e794fc39937dc72ac6a.png)
A.![]() | B.![]() | C.![]() | D.1 |
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