在△ABC中,角A,B,C的对边分别为a,b,c.已知向量
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101224733606622350/SYS201311012247336066223019_ST/0.png)
=(a+c,b-a),
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101224733606622350/SYS201311012247336066223019_ST/1.png)
=(a-c,b),且
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101224733606622350/SYS201311012247336066223019_ST/2.png)
.
(1)求角C的大小;
(2)若
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101224733606622350/SYS201311012247336066223019_ST/3.png)
,求角A的值.
考点分析:
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