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(2000•东城区)如果α是锐角,且cosα=,那么cos(90°-α)的值是(...
(2000•东城区)如果α是锐角,且cosα=
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232730893840004/SYS201310212327308938400016_ST/0.png)
,那么cos(90°-α)的值是( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232730893840004/SYS201310212327308938400016_ST/1.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232730893840004/SYS201310212327308938400016_ST/2.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232730893840004/SYS201310212327308938400016_ST/3.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232730893840004/SYS201310212327308938400016_ST/4.png)
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