已知
且
求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/25d185af7ac95e535811344cc481eed3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27691cee79e477c9d750a337f6c32fc8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6abc69c57972a4efb8301e3308ea9ca6.png)
2021高一·上海·专题练习 查看更多[2]
更新时间:2021-03-10 17:03:20
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【知识点】 已知两角的正、余弦,求和、差角的余弦解读
相似题推荐
解答题-问答题
|
适中
(0.65)
【推荐1】
中,内角
,
,
的对边分别是
,
,
,
,
,
.
(1)求
的值;
(2)若
为
中点,求
的长.
![](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/0b473fb8a71059050ab6ac67ec710850.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8301c4c5965ed1e67c6678b0a295e37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de894e4506f8d1252af61b722372b936.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
(2)若
![](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/03902478df1a55bc99703210bccab910.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
解题方法
【推荐2】已知
,
,函数
,且函数
的最小正周期为
.
(1)求函数
的表达式;
(2)设
,且
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d84a2783de4979bb5b8ab30d39810707.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b829f62ade9b887e108a184cedfebfe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4d8eb61222b37f7044c34551cd9c079.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e9fdc1f8ed0ae44b54a9a2a3aca2db4.png)
(1)求函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fe7d5809da02c15a43a0e9a898b9086.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/211ead7b4685ef34e3dc991e533d11c0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d77eb54c86b4208a75bacc5b98c7b9d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aefd06c239145a2b6ae87a955aa51414.png)
您最近一年使用:0次