Question

СРОЧНО!!!! ДАМ 35 БАЛЛОВ!!!
(а+b)²(x+y) - x (a+b)²-y(a+b) +(a+b) ²

Answer 1

$(a+b)^2(x+y)-x(a+b)^2-y(a+b)+(a+b)^2=\\\\=(a+b)^2(x+y-x+1)-y\, (a+b)=\\\\=(a+b)^2\, (y+1)-y\, (a+b)=\Big(a+b\Big)\Big((a+b)(y+1)-y\Big)=\\\\=\Big(a+b\Big)\Big(ay+by+a+b-y\Big)\ ;\\\\\\P.S.\ \ ...=(a^2+b^2)\, y+2aby-(a+b)\, y+a^2+b^2+2ab$