Question

Пример
(1/x^2-2xy+y^2-1/x^2-y^2):2y^2/xy+x^2=

Answer 1

=-2xy/(2y/x+x^3/x)=-2xy/((2y+x^3)/x)= -2yx^2(2y+x^3)= -x^2y/y+x^3