待定系数法是多项式恒等变形中常用的一种有效方法.其解题步骤是:先假定一个含有待定系数的恒等式,再根据多项式恒等的定义或性质列出方程(组);然后通过解方程(组),求出待定系数的值,从而使问题得到解决.该法常应用于因式分解、求函数的解析 The undetermined coefficient method is an effective method commonly used in polynomial identity transformation. The problem-solving steps are as follows: first assume an identity containing the undetermined coefficients, and then list the equations (groups) according to the definition or properties of the polynomial identity; then pass the solution The equation (group), the value of the undetermined coefficient, so that the problem is solved. This method is often used in factorization, the function of the analysis