This note is outcome of SP 2025 MATH 441. Differential Equations in UIUC, taught by professor Nikolaos Tzirakis.
The text book is Elementary Differential Equations and Boundary Value Problems, Ninth Edition.

Topic by chapter

CH1 Introduction: recap

CH2 First Order Differential Equations:

CH3 Second Order Linear Equations:

CH4 Higher Order Linear Equations:

CH5 Series Solutions of Second Order Linear Equations:

CH8 Numerical Methods: didn’t cover this chapter in class, but readme will cover some of it.

CH7 Systems of First Order Linear Equations:

CH9 Nonlinear Differential Equations and Stability: