1/2xy+y2+1+x2-1/2xy-2xy-1

1/2xy+y2+1+x2-1/2xy-2xy-1


what?



Decomposition factor: x2-2xy + y2-6x + 6y + 9


=(x-y)2-6(x-y)+9
=(x-y-3)2



(2x2-y2)-[2y2-(x2+2xy)]=______ .


3(X²-y²)+2xy