化简a-1分之a平方 -a -1

问题描述:

化简a-1分之a平方 -a -1

a²/(a-1)-a-1=a²/(a-1)-(a+1)=a²/(a-1)-(a+1)(a-1)/(a-1)=[a²-(a+1)(a-1)]/(a-1)=[a²-(a²-1)]/(a-1)=(a²-a²+1)/(a-1)=1/(a-1)