x3 + y3 + 3xy (x + y)
x2+y2 + 2xy
x3 + y3 + 3xy (x + y)
x2+y2- 2xy
x2 + y2 +z2 +2 (-xy - yz +zx)
(x+y)(x - y)
(x - y) (×2 +y2 + xy)
x3 + y3 + 3xy (x + y)
(x + y) (x2 + y2 - xy )
x2 + y2 +z2 + 2 (xy + yz + zx )
x3-y3 -3xy (x- y)
(x+y+z) (x2 + y2+z2 -xy -xz- yz)