Odpowiedzi

2009-10-16T14:42:30+02:00
2(x-x^2y)-(x-y-2)^2-4(x-y)+2(x^2y-xy)+y^2 =
2x - 2x^2y - x^2 - y^2 -4 -2xy - 4y -4x -4x +4y + 2 x^2y - 2xy +y^2 =
-6x - x^2 - 4xy - 4

(a-b-c)^2 = a^2 + b^2 + c^2 - 2ab + 2bc - 2ca