在△ABC中,角A,B,C所对的边分别是a,b,c,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100606571734396/SYS201311031006065717343016_ST/0.png)
=(sinA,sin B),
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100606571734396/SYS201311031006065717343016_ST/1.png)
=(cosB,cos A),
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100606571734396/SYS201311031006065717343016_ST/2.png)
•
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100606571734396/SYS201311031006065717343016_ST/3.png)
=-sin 2C.
(1)求角C的大小;
(2)若c=2
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100606571734396/SYS201311031006065717343016_ST/4.png)
,A=
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100606571734396/SYS201311031006065717343016_ST/5.png)
,求△ABC的面积S.
考点分析:
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103100606571734396/SYS201311031006065717343011_ST/4.png)
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其中正确命题的个数为( )
A.0
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