解题方法
1 . 在
中,内角
所对的边分别为
,且
,有下列四个结论:
①
;
②
是钝角三角形;
③![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edd44dadf874d7213471a3f4f825c176.png)
④
的最大内角是最小内角的2倍.
其中所有正确结论的序号为__________ .
![](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/2c5803f6fc09e7ac82fe1b06f57c64c3.png)
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c50dddd96130ec007785b8d138be8a12.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
③
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/edd44dadf874d7213471a3f4f825c176.png)
④
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
其中所有正确结论的序号为
您最近一年使用:0次
2 . 判断正误,正确的写正确,错误的写错误.
(1)正弦定理不适用于直角三角形.( )
(2)在
中必有
.( )
(3)在
中,若
,则必有
.( )
(4)在
中,若
,则必有
.( )
(5)正弦定理只适用于锐角三角形.( )
(6)在
中,等式
总成立.( )
(7)在一确定的三角形中,各边与它所对角的正弦的比是一定值.( )
(1)正弦定理不适用于直角三角形.
(2)在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e428e7a09732be85c1224e9c8f6a71c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76e313a46be46564540c03dc7c67cb40.png)
(3)在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e428e7a09732be85c1224e9c8f6a71c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d499e8ca8a0c2c810507e34456181577.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c4f5d3dd04ec5c50a81829dd8db2b8a.png)
(4)在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e428e7a09732be85c1224e9c8f6a71c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69318f2c6eafd050499702ce478d9dfa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f261f679d3bc2bb11b1b9ba215e707ea.png)
(5)正弦定理只适用于锐角三角形.
(6)在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e428e7a09732be85c1224e9c8f6a71c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76e313a46be46564540c03dc7c67cb40.png)
(7)在一确定的三角形中,各边与它所对角的正弦的比是一定值.
您最近一年使用:0次