5x²－x的四次方－4＝10（x²＋x－2）-(x的四次方-5x²+4)=10(x²+x-2)-(x²-1)(x²-4)=10(x+2)(x-1)-(x+1)(x-1)(x+2)(x-2)=10(x+2)(x-1)很明显x=1；x=-2是原方程的解,因为有因式为0,方程两...