3×2-3=____ 3×1=____
3×2+3=____ 3×3=____
---Do you know Tan Dun?
---Of course. He is a famous composer and won ______Oscar for his music in the film Crouching Tiger, Hidden Dragon in 2001.
—________!
如图,在△ABC中,AB=AC,D为BC上一点,连接AD,点E在AD上,过点E作EM⊥AB,EN⊥AC,垂足分别为M,N.下面四个结论:①如果AD⊥BC,那么EM=EN; ②如果EM=EN,那么∠BAD=∠CAD;③如果EM=EN,那么AM=AN; ④如果EM=EN,那么∠AEM=∠AEN.其中正确有( )
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