Question

-3x 2+12xy 2-6xy怎么算?

Answer 1

-3x^2+12xy^2-6xy

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

x^2(a-b)+y(a-b)

=(x^2+y)(a-b)

x^2(a-b)+y(b-a)

=x^2(a-b)-y(a-b)

=(x^2-y)(a-b)

5a^2b(x-y)^3-30ab^2(y-x)^2

=5a^2b(x-y)^3-30ab^2(x-y)^2

=5ab(x-y)^2[a(x-y)-6b]

=5ab(x-y)^2(ax-ay-6b)