解答:原式=﹙x²+x-1﹚²-4x²-4x+4+3 =﹙x²+x-1﹚²-4﹙x²+x-1﹚+4-1 =[﹙x²+x-1﹚-2]²-1 =[﹙x²+x-3﹚+1][﹙x²+x-3﹚-1] =﹙x²+x-2﹚﹙x²+x-4﹚
由(x²+x-1)²-4x²-4x+7=(x²+x-1)²-4(x²+x-1)+3=(x²+x-1-1)(x²+x-1-3)=(x²+x-2)(x²+x-4)=(x+2)(x-1)(x²+x-4).