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(2009•孝感)对于每个非零自然数n,抛物线y=x2-与x轴交于An,Bn两点...
(2009•孝感)对于每个非零自然数n,抛物线y=x
2-
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与x轴交于A
n,B
n两点,以A
nB
n表示这两点间的距离,则A
1B
1+A
2B
2+…+A
2009B
2009的值是( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021230527557687073/SYS201310212305275576870016_ST/1.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021230527557687073/SYS201310212305275576870016_ST/2.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021230527557687073/SYS201310212305275576870016_ST/3.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021230527557687073/SYS201310212305275576870016_ST/4.png)
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