二阶常系数线性微分方程的通解公式及应用

The Formula of Common Solution of Order-2 Differential Equation with Constant Coefficients and Applications

用常系数ｐ、ｑ及函数ｆ（ｘ）给出二阶常系数线性微分方程的通解公式。

This paper gives the formula of common solution of order-2 linear differential equation with constant coefficient by using p、q and f(x), and then directly gives the common solution of order-2 equation with parameter λ.