Question

求多项式x^3-3x^y+3xy^2-y^3减去多项式x^3+3x^y+3xy^2+y^3的差

jjjjjjjjjjj

Answer 1

(x^3-3x^y+3xy^2-y^3)-(x^3+3x^y+3xy^2+y^3)
=x^3-3x^y+3xy^2-y^3-x^3-3x^y-3xy^2-y^3
=-6x^y-2y^3

Answer 2

(x^3-3x^y+3xy^2-y^3)-(x^3+3x^y+3xy^2+y^3)
= x^3-3x^y+3xy^2-y^3-x^3-3x^y-3xy^2-y^3
= -6x^y-2y^3
= -2(3x^y+y^3)