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在圆x2+y2=5x内,过点(,)有n条弦的长度成等差数列,最小弦长为数列的首项...
在圆x
2+y
2=5x内,过点(
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102729743483599/SYS201311031027297434835008_ST/0.png)
,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102729743483599/SYS201311031027297434835008_ST/1.png)
)有n条弦的长度成等差数列,最小弦长为数列的首项a
1,最大弦长为a
n,若公差d∈[
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102729743483599/SYS201311031027297434835008_ST/2.png)
,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102729743483599/SYS201311031027297434835008_ST/3.png)
],那么n的取值集合为( )
A.{4,5,6,7}
B.{4,5,6}
C.{3,4,5,6}
D.{3,4,5}
考点分析:
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