椭圆
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101222837799704431/SYS201311012228377997044000_ST/0.png)
的中心到准线的距离是( )
A.2
B.3
C.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101222837799704431/SYS201311012228377997044000_ST/1.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101222837799704431/SYS201311012228377997044000_ST/2.png)
考点分析:
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已知函数
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101222837799301587/SYS201311012228377993015019_ST/0.png)
(a,b,c为常数,a≠0).
(Ⅰ)若c=0时,数列a
n满足条件:点(n,a
n)在函数
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101222837799301587/SYS201311012228377993015019_ST/1.png)
的图象上,求a
n的前n项和S
n;
(Ⅱ)在(Ⅰ)的条件下,若a
3=7,S
4=24,p,q∈N
*(p≠q),证明:
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101222837799301587/SYS201311012228377993015019_ST/2.png)
;
(Ⅲ)若c=1时,f(x)是奇函数,f(1)=1,数列x
n满足
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101222837799301587/SYS201311012228377993015019_ST/3.png)
,x
n+1=f(x
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101222837799301587/SYS201311012228377993015019_ST/4.png)
.
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设椭圆C:
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101222837799301587/SYS201311012228377993015018_ST/0.png)
(a>b>0)的左、右焦点分别为F
1,F
2,上顶点为A,过点A与AF
2垂直的直线交x轴负半轴于点Q,且
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101222837799301587/SYS201311012228377993015018_ST/1.png)
,若过A,Q,F
2三点的圆恰好与直线l:
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101222837799301587/SYS201311012228377993015018_ST/2.png)
相切.过定点M(0,2)的直线l
1与椭圆C交于G,H两点(点G在点M,H之间).
(Ⅰ)求椭圆C的方程;
(Ⅱ)设直线l
1的斜率k>0,在x轴上是否存在点P(m,0),使得以PG,PH为邻边的平行四边形是菱形.如果存在,求出m的取值范围,如果不存在,请说明理由;
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101222837799301587/SYS201311012228377993015018_ST/3.png)
,求λ的取值范围.
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已知函数f(x)=ax
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101222837799301587/SYS201311012228377993015017_ST/0.png)
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已知函数
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101222837799301587/SYS201311012228377993015016_ST/0.png)
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![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101222837799301587/SYS201311012228377993015016_ST/1.png)
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如图,在三棱锥P-ABC中,AC=BC=2,∠ACB=90°,侧面PAB为等边三角形,侧棱
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