(6х-х²)²-х²(х-1)(х+1)+6х(3+2х²)= 6x²-12x2+x4-x2(x2-1)+18x+12x3=6x2-12x2+4x-x4+x2+18x+12x3=-6x2+4x-x4+x2+18x+12x3=-6x2+22x+x4+12x3
(6х-х²)²-х²(х-1)(х+1)+6х(3+2х²)= 6x²-12x2+x4-x2(x2-1)+18x+12x3=6x2-12x2+4x-x4+x2+18x+12x3=-6x2+4x-x4+x2+18x+12x3=-6x2+22x+x4+12x3