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化简分式x/(x+y)+y/(x-y)-2xy/(x^2-y^2),再选择适当的x,y的值带入求值

题目详情
化简分式x/(x+y)+y/(x-y)-2xy/(x^2-y^2),再选择适当的x,y的值带入求值
▼优质解答
答案和解析
x/(x+y)+y/(x-y)-2xy/(x^2-y^2),
=[x(x-y)+y(x+y)-2xy]/(x^2-y^2)
=(x^2+y^2-2xy)/(x+y)(x-y)
=(x-y)/(x+y)
将x=1,y=0代入
=1/2