1- Introduction to Differential Equations
What even are these?
You obviously know what differentiation means by now. Differential equations are exactly that, equations that somehow involve a derivative.
Think about what the derivative actually is. The derivative is the rate of change of something. How something is changing.
Differential equations relate such derivatives. They're used to model real-life change. Say, population change, or, accumulation of interest, or, acceleration, and many many more other things.
All of these are forms of differential equations:
Differential equations have an "order". Much like orders in equations, or degrees of polynomials, the order of a differential equation is the highest order derivative in that equation.