名校
解题方法
1 .
的内角A,B,C的对边分别为a,b,c,已知
,
,
,则边
的值是_________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16c30701144de929b875643ec466889f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41c7895a304fbb8bfecb2cd72ab9f280.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03699cf3aa154fd75501ae7388d2539c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
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2 . 已知
,求
(1)
及
的值;
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9626e5b9db3f22a442f10fef71b76f83.png)
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a6aad40c02d5217af4535853938065b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6cc9750c313ee972124cb62c4a6fb7ea.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/626cca880ae8dfcda582fa50f9838a70.png)
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解题方法
3 . “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”.如图1,三个内角都小于
的
内部有一点
,连接
,求
的最小值.我们称三角形内到三角形三个顶点距离之和最小的点为费马点.要解决这个问题,首先应想办法将这三条端点重合于一点的线段分离,然后再将它们连接成一条折线,并让折线的两个端点为定点,这样依据“两点之间,线段最短”,就可求出这三条线段和的最小值.某数学研究小组先后尝试了翻折、旋转、平移的方法,发现通过旋转可以解决这个问题,具体的做法如图2,将
绕点
顺时针旋转
,得到
,连接
,则
的长即为所求,此时与三个顶点连线恰好三等分费马点
的周角.同时小组成员研究教材发现:已知对任意平面向量
,把
绕其起点沿逆时针方向旋转
角得到向量
.
,把点
绕点
沿顺时针方向旋转
后得到点
,求点
的坐标;
(2)在
中,
,借助研究成果,直接写出
的最小值;
(3)已知点
,求
的费马点
的坐标.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/231b861d6d1f1d0b9f52b041cb40eb62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19bb1063e139610045f3bca5ca0b2766.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7ed53a398b1d6b7b4abbb43a9abcf1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9524e3810e06dc781285f1289e75d653.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d5bca00fa20e6e80480b9d06d2e52ee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f850c705372b8a85489505da53239fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5643311f49a8c6f64b2a2788f79458e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f478a74bccc9b8d7745b08c5484f238.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abcb5d89b04570ceda2c29e11cb27a57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89756ef947f1add6a68efa8998430dc4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7de03fc9682ff77d327a5681010ab3b9.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/15615de1a6df206dbd081251f676578e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
(2)在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b11bf8ee11289d13cf5dd0ea9505e699.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7ed53a398b1d6b7b4abbb43a9abcf1f.png)
(3)已知点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24a65f35281b21fdfaf7c437fbd321eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
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解题方法
4 . 在平行四边形
中,
分别为
的中点,将三角形
沿
翻折,使得二面角
为直二面角后,得到四棱锥
.![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
平面
;
(2)求证:平面
平面
;
(3)求
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7e45e57ca15f89c5232f0a0607bfd50.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9df7fc746f8c4801d8f2f0471ba3297e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9a32bd7a1b78b5a0ec562c4025aea8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/105b820d3dc29726e33f3b835f60980d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e558262c7cb388c03fd669d1b545c29d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/638537c0a30676c73fea76c80e0f8bd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
(2)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec43f7352b3a8c194b4c37485fb4ffd8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
(3)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fc56c77464a17a1e97b568762a3e2c6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
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解题方法
5 . 如图,在正方体
中,
为棱
上的动点,
平面
为垂足,下列结论正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1e0bd4b30dc777ac9da80f6baa3eb31.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58b7e86d73300e4b2cb5a2138997a6ca.png)
A.![]() |
B.三棱锥![]() |
C.![]() |
D.![]() ![]() ![]() |
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6 . 已知
是两条不同的直线,
是平面,若![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/638537c0a30676c73fea76c80e0f8bd0.png)
,则
的关系可能为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/280860dd039e1305a5ccc455f63e8223.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/638537c0a30676c73fea76c80e0f8bd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd089bc2a70824f3c223b459490054e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/280860dd039e1305a5ccc455f63e8223.png)
A.平行 | B.垂直 | C.相交 | D.异面 |
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7 . 已知函数
,若不等式
对任意的
都成立,则实数
的取值范围为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8248e50bc59f52165d5ba1451ae8a25b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e9c599e8d420006448905acec2b8234.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb48434bdcafb5e084fc0b6396cb9469.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
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名校
8 . 数据
的方差
,则下列数字特征一定为0的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f1a2f40c3c0853c0d5a4150a9d3fc80.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8965c5e9e183417fb57c24d91f127c77.png)
A.平均数 | B.中位数 | C.众数 | D.极差 |
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今日更新
|
352次组卷
|
2卷引用:四川省成都市第七中学2023-2024学高一下学期6月月考数学试题
9 . 在
中,角
,
,
所对的边依次为
,
,
,已知
,则下列结论中正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4d5f963c3485870c100b3f09c9346dc.png)
A.![]() |
B.![]() |
C.若![]() ![]() ![]() |
D.若![]() ![]() ![]() ![]() |
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解题方法
10 . 在
中,
,点
满足
,且
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac4486890c4ba79dc50593b864800a8e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b12dcfb8f3fc0ac45d50782c3f248672.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7aaee7371c1e926fe02eddfde7ee33be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/825116eb345f5505ebc8c1cdb8a1f131.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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