(1/4a的平方-a+1)/(1-1/2a) =(1/4a²-a+1)/-(1/2a-1)=(1/2a-1)²/-(1/2a-1)=1/2a-1
(1/4a的平方-a+1)/(1-1/2a) =(a/2-1)²/(1-a/2)=(1-a/2)²/(1-a/2)=1-a/2
1-1不就等于0了么？
题目不清楚啊
