x^3+y^3=9x+y=3(x+y)(x^2-xy+y^2)=9x+y=3(x+y)(x^2-xy+y^2)/(x+y)=9/3x^2-xy+y^2=3x+y=3 =>x=3-y(3-y)^2-(3-y)y+y^2=39-6y+y^2-3y+y^2+y^2=33y^2-9y+6=0y^2-3y+2=0 (y-1)(y-2)=0y=1; y=2x=3-1=2x=3-2=1ответ: (2;1);(1;2)
x^3+y^3=9
x+y=3
(x+y)(x^2-xy+y^2)=9
x+y=3
(x+y)(x^2-xy+y^2)/(x+y)=9/3
x^2-xy+y^2=3
x+y=3 =>x=3-y
(3-y)^2-(3-y)y+y^2=3
9-6y+y^2-3y+y^2+y^2=3
3y^2-9y+6=0
y^2-3y+2=0
(y-1)(y-2)=0
y=1; y=2
x=3-1=2
x=3-2=1
ответ: (2;1);(1;2)