在△ABC中,内角A,B,C的对边分别是a,b,c,cos(C+
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231744316319811/SYS201311012317443163198015_ST/0.png)
)+cos(C-
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231744316319811/SYS201311012317443163198015_ST/1.png)
)=
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231744316319811/SYS201311012317443163198015_ST/2.png)
.
(I)求角C的大小;
(II)若c=
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231744316319811/SYS201311012317443163198015_ST/3.png)
,sinA=2sinB,求a,b.
考点分析:
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选做题:(考生可以在以下三个题任选一道题作答,如果多做以考生所作的第一道题为准)
(a) 不等式|x-4|-|x-2|>1的解集为
.
(b) 已知直线l的极坐标方程为:
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231744316319811/SYS201311012317443163198014_ST/0.png)
,圆C的参数方程为
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231744316319811/SYS201311012317443163198014_ST/1.png)
(θ为参数),那么直线l与圆C的位置关系为
.
(c) 如图已知圆中两条弦AB与CD相交于点F,E是AB延长线上一点,且
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231744316319811/SYS201311012317443163198014_ST/2.png)
.若CE与圆相切,则CE的长为
.
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已知向量
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231744316319811/SYS201311012317443163198013_ST/0.png)
=(
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231744316319811/SYS201311012317443163198013_ST/1.png)
,1),
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231744316319811/SYS201311012317443163198013_ST/2.png)
=(0,-1),
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231744316319811/SYS201311012317443163198013_ST/3.png)
=(k,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231744316319811/SYS201311012317443163198013_ST/4.png)
).若
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231744316319811/SYS201311012317443163198013_ST/5.png)
与
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231744316319811/SYS201311012317443163198013_ST/6.png)
共线,则k=
.
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231744316319811/SYS201311012317443163198012_ST/images0.png)
执行如图所示的程序框图,若输入A的值为2,则输出P的值为
.
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观察下列各式:1=1,1-3=-2;1-3+5=3;1-3+5-7=-4;…,则第8个等式为
.
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