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如图,△ABC中,∠ACB=90°,∠B=30°,AC=1,过点C作CD1⊥AB...
如图,△ABC中,∠ACB=90°,∠B=30°,AC=1,过点C作CD
1⊥AB于D
1,过点D
1作D
1D
2⊥BC于D
2,过点D
2作D
2D
3⊥AB于D
3,这样继续作下去,线段D
nD
n+1(n为正整数)等于( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103101408135710790/SYS201311031014081357107007_ST/images0.png)
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103101408135710790/SYS201311031014081357107007_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103101408135710790/SYS201311031014081357107007_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103101408135710790/SYS201311031014081357107007_ST/2.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103101408135710790/SYS201311031014081357107007_ST/3.png)
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