(x+1)(x+2)(x+3)(x+4)-3;x^2-x+y^2+y-2xy-6;

熱心網友

1.注意保持整體不分開:[(x+1)(x+4)][(x+2)(x+3)]-3=[(x^2+5x)+4)][(x^2+5x)+6]-3=(x^2+5x)^2 +10(x^2+5x)+21=(x^2+5x+3)(x^2+5x+7)2.(x-y)^2 -(x-y)-6=(x-y+2)(x-y-3)3.(a-b)^2-4(a-b)+4=(a-b-2)^2上面三題都是把某個單項式看成一個整體,從而簡化過程.4.根據二次項系數和常數項,不難看出因式分解如下:(6x^2+mx-1)=(3x-1)(2x+1) == m = 1