在△ABC中,角A、B、C所对的边分别为a、b、c,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102504359299017/SYS201311031025043592990015_ST/0.png)
=(2a,1),
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102504359299017/SYS201311031025043592990015_ST/1.png)
=(2b-c,cosC)且
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102504359299017/SYS201311031025043592990015_ST/2.png)
∥
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102504359299017/SYS201311031025043592990015_ST/3.png)
.
求:
(I)求sinA的值;
(II)求三角函数式
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102504359299017/SYS201311031025043592990015_ST/4.png)
的取值范围.
考点分析:
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