题目内容
求值:[2sin50°+sin10°(1+![](http://thumb.zyjl.cn/pic1/1898/img/06/41/57/189806415710012357/1.gif)
![](http://thumb.zyjl.cn/pic1/1898/img/06/41/57/189806415710012357/2.gif)
解:原式=(2sin50°+sin10°
=(2sin50°+2sin10°)·
cos10°
=2[sin50°cos10°+sin10°cos(60°-10°)]
=2sin(50°+10°)=2
·
=
.
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题目内容
求值:[2sin50°+sin10°(1+
解:原式=(2sin50°+sin10°
=(2sin50°+2sin10°)·
cos10°
=2[sin50°cos10°+sin10°cos(60°-10°)]
=2sin(50°+10°)=2
·
=
.