在△ABC中,角A,B,C的对边分别是a,b,c,且A,B,C成等差数列.
(1)若
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225443893214361/SYS201311012254438932143015_ST/1.png)
=-
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,b=
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,求a+c的值;
(2)求2sinA-sinC的取值范围.
考点分析:
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