在苏科版《数学》九年级上册第1章第3节有一个选学内容——一元二次方程的根与系数的关系,如果能掌握这个知识点,对于我们的解题将非常有帮助.一、根与系数关系的推导对于一元二次方程ax~2+bx+c=0(a≠0)来说,如果b~2-4ac≥0,那么它的两个根分别为 In the Soviet version of “Mathematics” ninth grade Chapter 1, Section 3 has an optional content - the root of the quadratic equation and the coefficient of the relationship, if we can grasp this point of knowledge, will be very helpful to our problem solving First, the derivation of the relationship between root and coefficient For the quadratic equation ax ~ 2 + bx + c = 0 (a ≠ 0), if b ~ 2-4ac ≥ 0, then its two roots were