在△ABC中,角A,B,C的对边分别为a,b,c,且满足(2a-c)cosB=bcosC.
(1)求角B的大小;
(2)设
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102633153975714/SYS201311031026331539757014_ST/0.png)
取最小值时,求
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102633153975714/SYS201311031026331539757014_ST/1.png)
值.
考点分析:
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102633153975714/SYS201311031026331539757010_ST/0.png)
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