牛顿迭代法（Newton's method）又称为牛顿-拉夫逊（拉弗森）方法（Newton-Raphson method），它是牛顿在17世纪提出的一种在实数域和复数域上近似求解方程的方法。多数方程不存在求根公式，因此求精确根非常困难，甚至不可能，从而寻找方程的近似根就显得特别重要。方法使用函数f(x)的泰勒级数的前面几项来寻找方程f(x) = 0的根。牛顿迭代法是求方程根的重要方法之一，其最大优点是在方程f(x) = 0的单根附近具有平方收敛，而且该法还可以用来求方程的重根、复根，此时线性收敛，但是可通过一些方法变成超线性收敛。另外该方法广泛用于计算机编程中。(The Newton iteration method (Newton's method) is also called the Newton Ravson (Raphson) method (Newton-Raphson method). It is a method proposed by Newton in seventeenth Century to approximate the equation in the real number field and the complex field. Most equations do not exist formula, so the accurate root is very difficult, even impossible, to find the approximate root is particularly important. The method uses the first few of the Taylor series of the function f (x) to find the root of the equation f (x) = 0. Newton iterative method is one of the important methods to solve the equation, its biggest advantage is in equation f (x) = 0 has quadratic convergence near the single, and the method can also be used for the root, complex equations, the linear convergence, but through some methods into super linear convergence. In addition, this method is widely used in computer programming)