因式分解: (1)x(x-y)+y(x-y)-(x-y)2 (2)-14xy-x2-49y2 (3)9(a+b)2-6(a+b)+1 (4)25(a-2b)2-64(b+2a)2 (5)x2(a+b)-(a+b) (6)(a2+9b2)2-
问题描述:
因式分解:
(1)x(x-y)+y(x-y)-(x-y)2
(2)-14xy-x2-49y2
(3)9(a+b)2-6(a+b)+1
(4)25(a-2b)2-64(b+2a)2
(5)x2(a+b)-(a+b)
(6)(a2+9b2)2-36a2b2.
答
(1)x(x-y)+y(x-y)-(x-y)2=(x-y)[x+y-(x-y)]=2y(x-y);(2)-14xy-x2-49y2=-(x2+49y2+14xy)=-(x+7y)2;(3)9(a+b)2-6(a+b)+1=[3(a+b)-1]2=(3a+3b-1)2;(4)25(a-2b)2-64(b+2a)2=[5(...