a²-3a+1=0a-3+(1/a)=0a+2+(1/a)=5a-2+(1/a)=1两式相除得(a+2+(1/a))/(a-2+(1/a))=5上下同时乘以a(a²+2a+1)/(a²-2a+1)=5(a+1)²/(a-1)²=5根号[(a+1)/(a-1)]=根号5根号[(a+1)/(a²-2)]=根...