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如图,已知△ABC,点D在边AC上,AD:DC=2:1,BD⊥AB,tan∠DB...
如图,已知△ABC,点D在边AC上,AD:DC=2:1,BD⊥AB,tan∠DBC=
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164818765557707/SYS201310221648187655577017_ST/0.png)
,则sin∠BAC的值是
.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164818765557707/SYS201310221648187655577017_ST/images1.png)
考点分析:
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