Question

有这样一道题:计算(2x^4-4x^3y-2x^2y^2)-(x^4-2x^2y^2+y^3)+(-x^4+4x^3y-

Answer 1

(2x^4-4x^3y-2x^2y^2)-(x^4-2x^2y^2+y^3)+(-x^4+4x^3y-y^3)

=2x^4-4x^3y-2x^2y^2-x^4+2x^2y^2-y^3-x^4+4x^3y-y^3

=2x^4-x^4-x^4+4x^3y-4x^3y-2x^2y^2+2x^2y^2-y^3-y^3

=4x^3y-4x^3y-2x^2y^2+2x^2y^2-y^3-y^3

=-2x^2y^2+2x^2y^2-y^3-y^3

=-y^3-y^3

=-2y^3

=-2*(-1)^3

=-2*(-1)

=2

化简结果与x无关,