在人教版初中《代数》第三册第十二章中,有一小节的内容是讲一元二次方程的根与系数的关系的。根与系数的关系可表述为“如果ax2+bx+c=0(a≠0)的两个根是x1,x2,那么x1+x2=-ba,x1·x2=ca”。对一元二次方程来说,根与系数的关系称为韦达定理。利用韦达定理,可以避免解方程的繁琐, In the 12th chapter of the third edition of the algebra of the People’s Education Press junior high school, there is a section on the relationship between the root and the coefficient of the quadratic equation. The relationship between the root and the coefficient can be expressed as “If the two roots of ax2 + bx + c = 0 (a ≠ 0) are x1, x2, then x1 + x2 = -ba, x1 x2 = ca”. For a quadratic equation, the relationship between the root and the coefficient is called the Vedic theorem. Using Vedic’s theorem can avoid the tediousness of solving the equations.