题目

a2—b2=2ab求a—b/a+b

提问时间：2020-11-03

答案

a2—b2=2ab(a/b)²-2(a/b)-1=0a/b=(2±√8)/2=1±√2(1)当a/b=1+√2时(a-b)/(a+b)=[(a/b)-1]/[(a/b)+1)]=√2/(√2+2)=√2-1(2)当a/b=1-√2时(a-b)/(a+b)=[(a/b)-1]/[(a/b)+1)]=-√2/(2-√2)=√2+1希望能帮到你,...