在△ABC中,角A,B,C的对边分别为a,b,c,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231806901108381/SYS201311012318069011083017_ST/0.png)
,C=2A.
(Ⅰ)求cosC的值;
(Ⅱ)若ac=24,求a,c的值.
考点分析:
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