Упростите выражение срочно надо

Question

Упростите выражение срочно надо

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Answer 1

7/(x^2-y^2)-5/(xy-x^2)-12/(x^2+xy)=
=7/((x-y)(x+y))-5/(x(y-x))-12/(x(x+y))=
=(7*x-5*(x+y)-12*(x-y))/(x(x+y)(x-y))=
=(7x-5x-5y-12x+12y)/(x(x+y)(x-Y))=
=(7y-10x)/(x(x+y)(x-y)