连接BE∵AB=AC∴∠ABC=∠ACB∵∠E=∠C∴∠E=∠ABC∵∠BAD=∠EAB∴△ABD∽△AEB∴AB/AE =AD/AB∴AB²=AD*AE又因为AC=AB所以AC²=AD*AE得证祝你学习天天向上~
证明:连接CE∵AB=AC∴∠ABC=∠B∵∠B=∠E(同弧所对的圆周角相等)∴∠ACB=∠E∵∠CAD=∠EAC∴△ACD∽△AEC∴AC/AE=AD/AC∴AB²=AD*AE