在Rt△ABC中,∠ABC=900,O是AB上一点,以O为圆心,OB为半径的圆与AB交于点E,与AC切于点D,且AD=2

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  • (1)⊙O的直径的长;AD^2=AE*AB,AB=4.⊙O的直径BE=AB-AE=3.(2)求BC的长;△ADO∽△ABC,OD/AD=BC/AB,BC=3.(3)求sin∠DBA的值△ADE∽△ABD,ED/AE=BD/AD,BD=2ED.BD^2+ED^2=AE^2,5ED^2=9,BD=3√5/5.sin∠DBA=ED/EB=...