Order of the Differential Equation

The order of the highest ordered derivative involved in a differential equation is called the order of the differential equation.

It may also be defined as: the order of a differential equation is the degree of the highest order derivative that occurs in the equation.

Examples:

• The order of the differential equation $$\frac{{dy}}{{dx}} = y{e^x}$$ is one.
• The order of the differential equation $$\frac{{{d^2}y}}{{d{x^2}}} + y = \sin x$$ is two.