解分因式(x+y)(x-y)-(x+y)^2 (x+y)^2+mx+my a(x-a)(x+y)^2-b(x-a)^2(
2个回答

解分因式(x+y)(x-y)-(x+y)^2

=(x+y)(x-y-x-y)

=-2y(x+y)

(x+y)^2+mx+my

=(x+y)^2+m(x+y)

=(x+y)(x+y+m)

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

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

= (x-a)(x+y)(ax+ay-bx+ab)

a^3-a

=a(a^2-1)

=a(a-1)(a+1)

a^2-49b^2

=(a+7b)(a-7b)

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

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

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

=(5x-y)(x-5y)