由解一元二次方程的因式分解法可知,若一元二次方程ax2+bx+c=0(a≠0)的两根是x1和x2,那么关于x的二次三项式ax2+bx+c必然可分解成a(x-x1)(x-x2)的形式,从而有ax2+bx+c=a(x-x1)(x-x2),这是关于一元二次方程的一个重要结论.这个结论当然也可以证明,因为当b2-4ac≥0时,由一元二次方程根与系数的关系,得x1+x2=-b/a,x1x2=c/a.因此 According to the factorization method of solving the quadratic equation of the unary quadratic equation, if two of the quadratic equations ax2 + bx + c = 0 (a ≠ 0) are x1 and x2, the quadratic equation ax2 + bx + c must be decomposed into the form a (x-x1) (x-x2) so that there is ax2 + bx + c = a (x- x1) (x- x2), which is an important quadratic equation This conclusion can of course also be proved, because when b2-4ac ≥ 0, the relationship between the root of the quadratic equation and the coefficient gives x1 + x2 = -b / a and x1x2 = c / a.