Phân tích x^4y^4 - z^4

x^4y^4-z^4
(x+y+z)^2-4z^2
a,(x+y+z)^2-4z^2
b,-1/9x^2+1/3xy-1/y^2
c,x^3y^2+125
d,8x^3-y^3-6xy(x-y)
e,(3x+2)^2-2(x-1)(3x+2)+(x-1)^2