一阶微分方程的积分因子解法

The Solution of First Order Differential Equation by Using Integrating Factor

本文推导出四种常见的一阶微分方程的积分因子的一般形式，其形式简单，易行，并介绍了用分组观察法求积分因子，该方法能解某些用常规方法不能解的微分方程。

The ordinary forms of intergrating factors in four kinds of the differential equation of first order are illustrated in this essay. The form is very simple and used easily. In this paper the method is given how to find the intergrating factor by observation, With the method, we can solve some equations that can not be solved with ordinary method.