Помогите номер 560 СРОЧНО!!!

Question

Помогите номер 560 СРОЧНО!!!

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Answer 1

2/xy : (1/x-1/y)ˇ2 - (xˇ2+yˇ2)/(x-y)ˇ2=
=2/xy: ((y-x)/xy)ˇ2- (xˇ2+yˇ2)/(x-y)ˇ2=
=2/xy . xˇ2yˇ2/(y-x)ˇ2  - (xˇ2+yˇ2)/(x-y)ˇ2=
=(2xy -(xˇ2+yˇ2))/(x-y)ˇ2=
=-(xˇ2-2xy+yˇ2)/(x-y)ˇ2=
=-(x-y)ˇ2/(x-y)ˇ2=-1