1 =(x+y)(7(x+y)2-5(x+y)-2)=(x+y)(x+y-1)(7(x+y)+2)
2 =(x2+2x)2+27(x2+2x)+162=(x2+2x+18)(x2+2x+9)
3 =(x-y)2-5(x-y)-6=(x-y-6)(x-y+1)
抱歉,提供到这里