解:(1)原式=(12x)2-(3y2)2=14x2-9y4;
(2)原式=(x2-14)(x2+14)=x4-116;
(3)原式=(x2-y2)(x2+y2)(x4+y4)=(x4-y4)(x4+y4)=x8-y8;
(4)原式=x2-y2+x2-4y2=2x2-5y2.
标签:3y2
解:(1)原式=(12x)2-(3y2)2=14x2-9y4;
(2)原式=(x2-14)(x2+14)=x4-116;
(3)原式=(x2-y2)(x2+y2)(x4+y4)=(x4-y4)(x4+y4)=x8-y8;
(4)原式=x2-y2+x2-4y2=2x2-5y2.
标签:3y2