1.(x^2+4)^2-16x^2=?2.-3x^3+6x^y-3xy^2=?

问题描述:

1.(x^2+4)^2-16x^2=?2.-3x^3+6x^y-3xy^2=?

1.
(x^2+4)^2-16x^2
=x^4-8x^2+16
=(x^2-4)^2
2.
-3x^3+6x^2y-3xy^2
=-3x(x^2-2xy+y^2)
=-3x(x-y)^2