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(2002•南京)如图,如果∠A是等边三角形的一个内角,那么cosA的值等于( ...
(2002•南京)如图,如果∠A是等边三角形的一个内角,那么cosA的值等于( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349023_ST/images0.png)
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349023_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349023_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349023_ST/2.png)
D.1
考点分析:
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