名校
解题方法
1 . 在
中,内角A,B,C的对边分别为a,b,c,BC,AC边上的两条中线AM,BN相交于点P.
,
,用
,
表示
;
(2)证明:
;
(3)若
,
,
,求∠MPN的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f3adc4ed291596abf3bb93ae7a075d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cc03a3ba496faee748a8d63e5d4fa92.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64c5562bd4d1b54424330cb6329cd79d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b45ba716f03748c19b7ce2f99af536ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7239b3f2d88c2e45e17e5de9ae1a332.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad18017b1c4f15f274f44bd4410a8b07.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d2c15801fee2405573677484f5dcfa4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/addb8e20db1fbb40f17dea52f951b907.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b57fdd2a3642716fcf5100011eb3ec88.png)
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名校
解题方法
2 . 对于
,有如下判断,其中正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
A.若![]() ![]() |
B.若![]() ![]() |
C.若![]() ![]() |
D.若![]() ![]() |
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3 . 如图,平行四边形
中,
,
.现将
沿
起,使二面角
大小为120°,则折起后得到的三棱锥
外接球的表面积为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1cc201327a8ee3fd646948d3f0c5d9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/05d35d8d8bb0dc17f2f86fe5b230a2b8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/661ff55b5ebbadfb600989af3cfce2fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/282d4a8c3476b2b81e3fd73898e64539.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3931333820859378ea6723ff3075189.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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515次组卷
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2卷引用:浙江省重点中学四校2023-2024学年高一下学期5月联考数学试题
名校
解题方法
4 . 在棱长均相等的四面体
中,
为棱
(不含端点)上的动点,过点
的平面
与平面
平行.若平面
与平面
,平面
的交线分别为
,则
所成角的正弦值的最大值为________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7abd284f76d9f5769bc189508ce2572b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4eb7e9ad5486cf1c5e506b20c5469e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/280860dd039e1305a5ccc455f63e8223.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/280860dd039e1305a5ccc455f63e8223.png)
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5 . 已知
分别为
的边
上的点,线段
和
相交于点
,若
,
,
,其中
.则
的最小值为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91e1e4115d78e625e9e0f47cdade3286.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dec2ca6438c82b43f746057d8129885.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9be878f5bdce9a3e9939a4ae743c803b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b1174877b02d3c54c58314fa7cd1218.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d83463cbe4e6b434ce448c053cae70ae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/761e8ff96c96ac26682b521288a01bee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23c227da7ad9d24ae3e3740febf9f293.png)
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6 . 海宝塔位于银川市兴庆区,始建于北朝晚期,是一座方形楼阁式砖塔,内有木梯可盘旋登至顶层,极目远眺,巍巍贺兰山,绵绵黄河水,塞上江南景色尽收眼底.如图所示,为了测量海宝塔的高度,某同学(身高173cm)在点
处测得塔顶
的仰角为
,然后沿点
向塔的正前方走了38m到达点
处,此时测得塔顶
的仰角为
,据此可估计海宝塔的高度约为__________ m.(计算结果精确到0.1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29e0c2455a9e796bba6861503f0fe31b.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/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ea06b78df3f0847f358714357a18d30.png)
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217次组卷
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3卷引用:福建省福州市部分学校教学联盟2023-2024学年高一下学期期末模拟考试数学试题
福建省福州市部分学校教学联盟2023-2024学年高一下学期期末模拟考试数学试题(已下线)【高一模块一】难度8 小题强化限时晋级练(较难2)宁夏回族自治区银川九中、平罗中学、贺兰二高、西吉中学2024届高三第四次模拟考试联考数学(文)试题
名校
解题方法
7 . “不以规矩,不能成方圆”出自《孟子・离娄章句上》.“规”指圆规,“矩”指由相互垂直的长短两条直尺构成的方尺,是古人用来测量、画圆和方形图案的工具.敦煌壁画就有伏羲女娲手执规矩的记载(如图(1))今有一块圆形木板,以“矩”量之,如图(2).若将这块圆形木板截成一块四边形形状的木板,且这块四边形木板的一个内角
满足
,则这块四边形木板周长的最大值为______ (单位:厘米)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25f8783429be686df75afcd56e847dfa.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/6/7/7b52b3da-7f3b-4a55-8a4e-8b9121cb4e82.jpg?resizew=283)
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8 . 如图,已知两座山的海拔高度
米,
米,在BC同一水平面上选一点
,测得
点的仰角为
点的仰角为
,以及
,则M,N间的距离为____________ 米.(结果保留整数,参考数据
)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd9cbea10075834324a661a4514c4e02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/664ef8298f9c6eef667861e1da9bd8a3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96826763a0ea52872b73c25460e2d973.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c030b25575d683af91c06e6a3e4f463.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08fddda4936a9be50e32b18b4c79e8b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31e37ef1a48dbbf1c399ece970d3a92c.png)
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9 . 如图、某港口O要将一件重要物品用小艇送到一艘正在航行的轮船上,在小艇出发时,轮船位于港口O北偏西
方向且与该港口相距
的A处,并以
的航行速度沿正东方向匀速行驶,假设该小艇沿直线方向以
的航行速度匀速行驶,经过
与轮船相遇.(假设水面平静)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/6/19/6b7939b6-56a3-4ae7-90d0-7b6d0d796451.png?resizew=168)
(1)要使相遇时小艇的航行距离最短,小艇的航行速度应为多少?
(2)假设小艇的速度最快只能达到
,要使小艇最快与轮船相遇,应向哪个方向航行?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6b86c22b670a8e9f3896f9e8883fbbb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7d1525355976915a23b0a3050e6a687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cdde1bd791be76f4dfc0116f5c8dacce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6737e5a65b0067db9bdac02a52de7131.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3ee630252dc9ec9c8453d1561a81743.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/6/19/6b7939b6-56a3-4ae7-90d0-7b6d0d796451.png?resizew=168)
(1)要使相遇时小艇的航行距离最短,小艇的航行速度应为多少?
(2)假设小艇的速度最快只能达到
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d568215783a27afd4041395551623c4a.png)
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2卷引用:陕西省渭南市富平县蓝光中学2023-2024学年高一下学期6月月考数学试题
解题方法
10 . 在
中,角A,B,C的对边分别为a,b,c,若
,
,则
面积的最大值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e258ab9e600435b37465092243d99f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43b86d43790babcdbbdc03493ee70928.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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