如图,已知锐角△ABC中,∠A,∠B,∠C的对边分别是a,b,c.
(1)试说明:S△ABC=
absinC;
(2)若a=30cm,b=36cm,∠C=30°,求△ABC的面积.
(1)试说明:S△ABC=
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
(2)若a=30cm,b=36cm,∠C=30°,求△ABC的面积.
![](https://img.xkw.com/dksih/QBM/2018/8/16/2011750832824320/2049752980586496/STEM/562701c6f46e4b999caf2fbd5205771b.png?resizew=128)
19-20九年级上·山东·课后作业 查看更多[1]
(已下线)专题2.2 30°,45°,60°角的三角比 分层练习2-2018-2019学年九年级上学期数学教材(青岛版)
更新时间:2018-10-09 09:36:01
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【知识点】 三角函数综合
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【推荐2】已知AB为⊙O的直径,OC⊥AB,弦DC与OB交于点F,在直线AB上有一点E,连接ED,且有ED=EF.
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