Помогите найти числовое значение выражения: (x/x-y+2xy/X^2-2xy+y^2) * (2x/x+y-1) Пояснения: / - дробь ^-степень

[x / (x-y) + 2xy / (x^2-2xy+y^2) ] * {2x / (x+y) - 1} =

= [x / (x-y) + 2xy / (x-y) ^2] * [{2x - (x+y) } / (x+y) ] =

= [ {x (x-y) + 2xy} / (x-y) ^2] * [ (x-y) / (x+y) ] =

= [ (x^2-xy+2xy) / (x-y) ^2 * [ (x-y) / (x+y) ]

= [ (x^2+xy) ] / [ (x-y) (x+y) ]=

= x (x+y) / [ (x-y) (x+y) ]=

=x / (x-y) = (-2) / (-2+1) = (-2) / (-1) = 2