已知二次方程的实根分布在给定的区间内,求方程中参数的取值范围问题,称为二次方程根分布问题.二次方程根分布问题在高中数学中应用十分广泛,许多数学问题可以转化为二次函数根分布问题.解二次方程根分布问题的基本原则是数形结合,画出一个符合条件的二次函数图象,由图象看区间端点的函数值的符号,看对称轴的位置,判别式 It is known that the real root of the quadratic equation is distributed in a given interval and the problem of the range of parameters in the equation is called the root distribution problem of quadratic equations.The root distribution problem of quadratic equations is widely used in high school mathematics, Mathematical problems can be transformed into quadratic function root distribution problem. The basic principle of solution of quadratic root distribution problem is the combination of number and form a quadratic function to meet the conditions of the image to see the end of the function of the value of the symbol , Look at the position of the symmetry axis, discriminant