名校
1 . 已知
,
是
的中点.
(1)若
,求向量
与向量
的夹角的余弦值;
(2)若
是线段
上任意一点,且
,求
的最小值;
(3)若点
是
内一点,且
,求
的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e46a4e894ae759de1877c4d24cd135fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87909c6df58fe648cd8daa2f662a260b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18acebeae8cc30bd05d6dfd5f0f2e737.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e88bca29b1406f27f1913b7f25fb483.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d50703c46b6153945d718b198f03b4b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ff6beb20606e85d6ff7f155907da9aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/721ed4ebca1b4223d382b6dc71ce0971.png)
(3)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7cbce11aa19b8bd2bf6ee5a834e005de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a528f40cca3187bafc597fe2228d681.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8448f2cc52d0f48e3dcb5d44c4cead1e.png)
您最近一年使用:0次
2020-06-16更新
|
256次组卷
|
3卷引用:山西省怀仁市第一中学2020-2021学年高一下学期期中数学试题
解题方法
2 . 设
是锐角三角形,三个内角
所对的边分别记为
,并且
.
(1)求角
的值;
(2)若
,求
(其中
.
![](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)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81b89591720c9d98781c19a67dd93a38.png)
(1)求角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ff81216d148f0b212b3301f8816d87b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/632244ea6931507f8656e1cc3437d392.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ab5edfec1af21a2e3560f5d90fbb58e.png)
您最近一年使用:0次
2016-12-04更新
|
297次组卷
|
2卷引用:2016届山西右玉一中高三冲刺压轴卷四数学(理)试卷