∠1=∠2是不是就是AD是∠BAC的角平分线啊证明：在AB上取点E,是AC = AE.连结ED∵AE = AC,∠1 = ∠2,AD = AD∴△AED≌△ACD∴CD = ED,∠C = ∠AED∵AB = AC+CD = AE + EB∴CD = BE∴ED = BE∴∠B = ∠EDB∵∠AED = ∠B...