(y^4+y^3)(y^2-y)=y^3(y^2+1)(y-1)
(y^4+y^3)(y^2-y)=y^3(y^2+1)(y-1) y^3(y+1)y(y-1)=y^3(y^2+1)(y-1) y(y+1)=y^2+1 y^2+y=y^2+1 y=1 Ответ: y=1