问题
解答题
(1)3y2-6xy
(2)25x2-16y2
(3)3a2-6a+3
(4)x2(a-b)2-y2(b-a)2.
答案
(1)3y2-6xy=3y(y-2x);
(2)25x2-16y2=(5x+4y)(5x-4y);
(3)3a2-6a+3,
=3(a2-2a+1),
=3(a-1)2;
(4)x2(a-b)2-y2(b-a)2,
=(a-b)2(x2-y2),
=(a-b)2(x+y)(x-y).