Differential Equations. All Basics for Physicists.

https://www.youtube.com/watch?v=9h1c8c29U9g&list=PLTjLwQcqQzNKzSAxJxKpmOtAriFS5wWy4
00:00​ Why do I need differential equations?
00:30 What is a differential equation?
03:24​ Different notations of a differential equation
05:03​ What should I do with a differential equation?
06:15 How to identify a differential equation
07:11​ What are coupled differential equations?
08:36​ Classification: Which DEQ types are there?
15:48​ What are DEQ constraints?
18:08 Difference between boundary and initial conditions
20:39​ Solving method #1: Separation of variables
23:03​ Example: Radioactive Decay law
24:49​ Solving method #2: Variation of constants
28:02​ Example: RL Circuit
31:33​ Solving method #3: Exponential ansatz
37:17 Example: Oscillating Spring
43:21 Solving method #4: Product / Separation ansatz
More: https://en.fufaev.org/differential-equations

Books by Alexander Fufaev:
1) Equations of Physics: Solve EVERY Physics Problem
https://en.fufaev.org/physics-equations-book
2) Alexander Fufaev and His Never Ending Story:
https://en.fufaev.org/lifestory