Respuesta :

gmany

[tex]\dfrac{x}{x-y}+\dfrac{y}{x+y}=\dfrac{x(x+y)}{(x-y)(x+y)}+\dfrac{y(x-y)}{(x-y)(x+y)}\\\\=\dfrac{x^2+xy+xy-y^2}{(x-y)(x+y)}=\dfrac{x^2+2xy-y^2}{x^2-y^2}\\\\Used:\ a^2-b^2=(a-b)(a+b)[/tex]

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