根据《义务教育数学课程标准》(2011年版)选学内容的教学要求,根与系数的关系学生只了解即可,并不要求利用根与系数的关系进行复杂的关系式变形.但是,由于根与系数的关系是由根派生出来的,所以,我们遇到复杂的关系式,不妨回到根的定义,可能会更简捷.兹举两例供参考.例1(2014年菏泽中考题)已知关于x的一元二次方程x~2+ax+b=0有一非零实根-b,则a-b值为___. According to the compulsory education mathematics curriculum standards (2011 edition) of the elective content of the teaching requirements, the relationship between root and coefficient students can only understand, does not require the use of root and coefficient of the relationship between the complex relationship deformation.However, as the root And the relationship between the coefficients is derived from the root, so we encounter complex relationships, may wish to return to the definition of the root, may be more simple. I cite two cases for reference. Knowing that the quadratic equation x ~ 2 + ax + b = 0 for x has a non-zero real root -b, the ab value is ___.