4.1.1

Instructor: In order to determine the order of a differential equation, we need to identify the highest order of any derivative of our unknown function that appears in our equation. So in part A, the highest order derivative we have is a first order. So this is a first order differential equation. 

Similarly, part B, the highest order derivative we have is a third derivative. So the order of that differential equation is 3. Last, the order of part C, the highest order derivative we have of our y function is a fourth derivative. And so the order is 4.