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问题: 探究题

解答:

相信(1)比较容易,而且也可以作为(2)的特例来看待
下面仅就(2)证明如下:

过C作CF∥AB交AE延长线与F

CF∥AB==>BE/CE=AB/CF
∠BAC=90,AE⊥BD==>∠ABD=∠CAF
∠BAC=90,CF∥AB==>∠BAD=∠ACF=90
==>△ABD∽△CAF
==>AB/AC=AD/CF=m
BD为中线==>AD=1/2AC
==>CF=AC/(2m)
==>BE/CE=AB/[AC/(2m)]=2m*AB/AC=2m^2
==>BE=2m^2*CE