因式分解(x-y)^2-4(x-y)-a^2+4

因式分解(x-y)^2-4(x-y)-a^2+4


(x-y)^2-4(x-y)-a^2+4移項
=(x-y)^2-4(x-y)+4-a^2完全平方
=[(x-y)-2]²;-a²;
=(x-y-2)²;-a²;平方差
=(x-y-2+a)(x-y-2-a)



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


(a-b)(x-y)-(b-a)(x+y),=(a-b)(x-y)+(a-b)(x+y),=(a-b)(x-y+x+y),=2x(a-b).



a3(x-y)-3a2b(y-x)因式分解為______.


a3(x-y)-3a2b(y-x)=a3(x-y)+3a2b(x-y)=a2(x-y)(a-3b).故答案為:a2(x-y)(a-3b).



因式分解:9-a²;+4ab-4b²;