中文说明：
matlab开发环境下，牛顿迭代法解非线性方程组，使用者把非线性方程组的M文件fx1(x)和非线性方程组导数的M文件dfx1(x)相应代入即可。
English Description：
In the matlab development environment, Newton iterative method is used to solve the nonlinear equations. The user can substitute the m file FX1 (x) of the nonlinear equations and the m file dfx1 (x) of the derivatives of the nonlinear equations