蓝1976
春芽
共回答了15个问题采纳率:80% 举报
1、原式=[4(x+y)]^2-[6(x-y)]^2
=[4(x+y)+6(x-y)][4(x+y)-6(x-y)]
=(10x-2y)(10y-2x)
=4(5x-y)(5y-x)
2、原式=a^4+2a^2b^2+b^4-4a^2b^2
=a^4-2a^2b^2+b^4
=(a^2-b^2)^2
=[(a+b)(a-b)]^2
=(a+b)^2(a-b)^2
3、原式=(x+y)^2-4(x+y)(x-y)+[2(x-y)]^2
=[(x+y)-2(x-y)]^2
=(3y-x)^2
1年前
2