Question

如图,在直角三角形ABC中,角C=90度BC=2ACAD是∠BAC的平分求证,AB＋2BD＝5AC拜托各位了 3Q

Answer 1

设AC = 1 ,可得：BC = 2 ,AB = √5 .已知,AD是∠BAC的平分线,可得：BD/CD = AB/AC = √5 ,可求得：BD = (1/2)(5-√5) ,CD = (1/2)(√5-1) ,所以,AB+2BD = 5 = 5AC .