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已知三角形△ABC的三边长成公差为2的等差数列,且最大角的正弦值为,则这个三角形...
已知三角形△ABC的三边长成公差为2的等差数列,且最大角的正弦值为
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102429882537305/SYS201311031024298825373004_ST/0.png)
,则这个三角形的周长是( )
A.18
B.21
C.24
D.15
考点分析:
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