Question

упрастите выражения
пожалуйста

Answer 1

1) (x+y-(x-y))/(x+y)(x-y)=
=(x+y-x+y)/(x+y)(x-y)=
=2y/(x+y)(x-y)
2) (2y*(x+y)(x-y))/
/(x+y)(x-y)*y²=2/y