已知第二象限的角
,并且
.
(1)化简式子
并求值;
(2)若
,请判断实数
的符号,计算
的值.(用字母表示即可)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9bc052a11cf1a01445992672dde2836.png)
(1)化简式子
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbb8eb9cecd01e689154fea08349041f.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e7a90338c77f8b2353435238f007bb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1144bee23c2152fb42fc1c376d6bbff6.png)
更新时间:2018-07-18 08:08:54
|
相似题推荐
解答题-问答题
|
适中
(0.65)
名校
【推荐2】在
中,角
、
、
所对的边分别为
、
、
.
(1)若
、
、
成等比数列,且
,求
的值;
(2)若
、
、
成等差数列,且
,求
的周长
的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0faed94a64b2dcfc6801b4fca0f16675.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)
(1)若
![](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/55493e331f88d3d1c396e92b46c97ecd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44a5ac2c5aa4d08c4ca88546a581649a.png)
(2)若
![](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/03837b3769eda7f0d3804cc5ad4a6d60.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0faed94a64b2dcfc6801b4fca0f16675.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
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解答题-问答题
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适中
(0.65)
名校
解题方法
【推荐1】已知
是方程
的根.求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8f798a9af75a091a8be0b71f2038260.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9a4d916e9b8739a4dc7176a3c2cff41.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/311768fb530b36f33fdf83392efbe81e.png)
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【推荐2】利用正切函数的单调性比较下列各组中两个函数值的大小:
(1)
与
;
(2)
与
;
(3)
与
;
(4)
与
.
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891aa826eeb98485634fc0826800758a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44207f1f1de4df2ff9ef37afc5b94f90.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/694cb651a2ad140f0b86e641e8df7a88.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a33056d5d9a875761f1b2f0c008f8ff.png)
(3)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6370641c70fa22f3dda7c2b6b5902f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33158b404d37dacc971204e64f6b96ef.png)
(4)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72415c1c55c5926cd48932563148a8ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da6ba0e56d83957890fccc9dd1f2388a.png)
您最近一年使用:0次
解答题-问答题
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适中
(0.65)
【推荐1】设
是锐角三角形,三个内角
,
,
所对的边分别记为
,
,
,并且
.
(Ⅰ)求角
的值;
(Ⅱ)若
,
,求
,
(其中
).
![](https://img.xkw.com/dksih/QBM/2015/4/29/1572086904897536/1572086911000576/STEM/908f4a9e2aa74b80b20fc5aef4efb39e.png)
![](https://img.xkw.com/dksih/QBM/2015/4/29/1572086904897536/1572086911000576/STEM/6d48a014ff234de79114ed8dcd2571d1.png)
![](https://img.xkw.com/dksih/QBM/2015/4/29/1572086904897536/1572086911000576/STEM/76fb6a46c28247fd9df78ec8c0673169.png)
![](https://img.xkw.com/dksih/QBM/2015/4/29/1572086904897536/1572086911000576/STEM/dbb72c6eda604e8c94d8fe071154065b.png)
![](https://img.xkw.com/dksih/QBM/2015/4/29/1572086904897536/1572086911000576/STEM/81fde4e73a164844ab3e0a3e5832002b.png)
![](https://img.xkw.com/dksih/QBM/2015/4/29/1572086904897536/1572086911000576/STEM/6fca51985eb549068f3ff84d4368aed9.png)
![](https://img.xkw.com/dksih/QBM/2015/4/29/1572086904897536/1572086911000576/STEM/208e56b52964448b954e130261b202da.png)
![](https://img.xkw.com/dksih/QBM/2015/4/29/1572086904897536/1572086911000576/STEM/f4745d2d1c804cd5afe1bff92c5e6038.png)
(Ⅰ)求角
![](https://img.xkw.com/dksih/QBM/2015/4/29/1572086904897536/1572086911000576/STEM/6d48a014ff234de79114ed8dcd2571d1.png)
(Ⅱ)若
![](https://img.xkw.com/dksih/QBM/2015/4/29/1572086904897536/1572086911000576/STEM/546926e5b11146478c2c3fe11b3def91.png)
![](https://img.xkw.com/dksih/QBM/2015/4/29/1572086904897536/1572086911000576/STEM/94852f7e591c42e18e3a61a5ee35e4c5.png)
![](https://img.xkw.com/dksih/QBM/2015/4/29/1572086904897536/1572086911000576/STEM/6fca51985eb549068f3ff84d4368aed9.png)
![](https://img.xkw.com/dksih/QBM/2015/4/29/1572086904897536/1572086911000576/STEM/208e56b52964448b954e130261b202da.png)
![](https://img.xkw.com/dksih/QBM/2015/4/29/1572086904897536/1572086911000576/STEM/4edbc80154de4d42bb09da9a8364a33a.png)
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解答题-问答题
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适中
(0.65)
解题方法
【推荐2】记
的内角
的对边分别为
,已知
.
(1)若
,求
;
(2)若
,求
的面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce7af7c5df749c6fa9bbe87faa72c66d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/88f2599ca8b6b683e57a82699c8b1ebb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b324971e78579326d9d058bfd893079.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fc25b6968fe6730d8b1988a602c77d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1311f32edf13f8caee5edb03f24a7ba.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e207b2baf056a7d6a6bde1f23bf12bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
您最近一年使用:0次