An important inequality is used to establish some criteria for the oscillation of forced difference equation and it is generalized to higher order.
借助一个重要的不等式研究一类带有强迫项的时滞差分方程的振动性，并推广至高阶的情形。
2
Among ordinary differential equation equations, differential inequality is a useful tool which helps research on properties of equation-solving.
在常微分方程论中，微分不等式是研究方程解的各种属性的有用工具。
3
Finite Elemnent-Linear Complementary Equation is established for analysis of elastoplastic thin plate-bending problems based on variational inequality principle.