litanalove В скобках

6/(x-y) -5/(x+y) =(6(x+y) -5(x-y)) /(x-y)(x+y) =(6x +6y -5x +5y) /(x-y)(x+y) =(x +11y) /(x -y)(x +y)

умножение

(x+11y)*(x-y) /(x-y)(x+y)*(x+11y) =1/(x +y)

ответ: 1 /(x+y)