What is the Order of a differential equation?
The order of a differential equation is a highest order of
derivative in a differential equation.
For example, let us assume a differential expression like
this.
d2y/dx2 + (dy/dx)3 + 8 = 0
In this differential equation, we are seeing highest derivative
(d2y/dx2) and also seeing the highest power i.e 3 but it is power
of lower derivative dy/dx.
According to the definition of differential equation, we should
not consider highest power as order but should consider the highest
derivative's power i.e 2 as order of the differential equation.
Therefore, the order of the differential equation is second
order.