已知△ABC的两边长分别为AB=25,AC=39,且O为△ABC外接圆的圆心.(注:39=3×13,65=5×13)
(1)若外接圆O的半径为
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101051457280464/SYS201311031010514572804018_ST/0.png)
,且角B为钝角,求BC边的长;
(2)求
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101051457280464/SYS201311031010514572804018_ST/1.png)
的值.
考点分析:
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1=2,
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.
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(A>0,ω>0)的最大值为3,其图象相邻两条对称轴之间的距离为
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,
(1)求函数f(x)的解析式;
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,则
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101051457280464/SYS201311031010514572804016_ST/3.png)
,求α的值.
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101051457280464/SYS201311031010514572804015_ST/images0.png)
如图,⊙O的直径AB=6cm,P是AB延长线上的一点,过p点作⊙O的切线,切点为C,连接AC,若∠CPA=30°,PC=
cm.
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在极坐标系中,直线ρsin(θ+
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101051457280464/SYS201311031010514572804014_ST/0.png)
)=2被圆ρ=4截得的弦长为
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101051457280464/SYS201311031010514572804013_ST/0.png)
的图象形如汉字“囧”,故称其为“囧函数”.下列命题正确的是
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⑤“囧函数”的图象与直线y=kx+b(k≠0)的图象至少有一个交点.
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