名校
1 . 在
中,“
”是“
为锐角三角形” 的( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5aab12c40441153db932ae4149e5547.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
A.充分不必要条件 | B.必要不充分条件 |
C.充要条件 | D.既不充分也不必要条件 |
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名校
解题方法
2 . “费马点”是由十七世纪法国数学家费马提出并征解的一个问题.该问题是:“在一个三角形内求作一点,使其与此三角形的三个顶点的距离之和最小.”意大利数学家托里拆利给出了解答,当
的三个内角均小于
时,使得
的点
即为费马点;当
有一个内角大于或等于
时,最大内角的顶点为费马点.试用以上知识解决下面问题:已知
的内角
所对的边分别为
,
(1)若
,
①求
;
②若
,设点
为
的费马点,求
;
(2)若
,设点
为
的费马点,
,求实数
的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6c0927afc571a7c966c98192040979e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e8036a881da6a4eef036529028a11d8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6c0927afc571a7c966c98192040979e.png)
![](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/76f0649064a085fb74c997fb507a9b6d.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2766e2c697dbefcef5f9fc0f43d7efed.png)
①求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
②若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44ac38c5cc951497a4a37778b191bcce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3b8f8a1e38db0e55b9b1934569b24e74.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1aa1240d911a4276d86ea2ac218084c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b01862dfc85d45102a1343c36cb6dfe5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36a1b09c653185842513e24ebba60bb3.png)
您最近一年使用:0次
2024-03-25更新
|
1342次组卷
|
7卷引用:北京市顺义区第一中学2023-2024学年高一下学期期中考试数学试卷
3 . 如图,正三角形
边长为2,
是线段
上一点,过
点作直线
的垂线,交线段
的延长线于点
,则
的最大值为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b09c2a26eb63ff4de7576d4f153b7c4.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/21/4790cb42-9464-475e-aa17-b3015a2a08ee.png?resizew=136)
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2020-01-10更新
|
415次组卷
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2卷引用:2020年1月中学生标准学术能力诊断性测试诊断性测试文科数学试卷
名校
4 . 对于非零向量
,定义运算“
”:
,其中
为
的夹角.设
为非零向量,则下列说法错误 的是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/445bc991a4a02776199f7412c84f37c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2468403b3eba9e40bfa36f464e927738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd05525b42968591698afb4a0b875ba7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/445bc991a4a02776199f7412c84f37c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab7cad34fccd0fe584087604e863f352.png)
A.![]() | B.![]() |
C.若![]() ![]() | D.![]() |
您最近一年使用:0次
2018-03-07更新
|
429次组卷
|
3卷引用:北京市汇文中学2023-2024学年高一下学期期中考试数学试卷