A fourth-order differential equation is one where the highest derivative of the function is a fourth derivative. In the context of these problems, the independent variable is usually time, denoted by , and the dependent variable is a function of time, such as . Fourth-order equations are common in physics and engineering, especially with systems that involve oscillations or wave functions.
A general fourth-order differential equation can be represented as:
Here, is the fourth derivative of , and are constant coefficients. The provided equation is a linear homogeneous equation meaning it equals zero and has constant coefficients. Understanding the order of a differential equation helps categorize and apply appropriate methods for finding its solutions.