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Differential Equations

Analysis

Ordinary differential equations: first- and second-order methods, systems, Laplace transforms, series and Frobenius solutions, qualitative theory, Fourier series and numerical methods.

15 topics · 76 lessons about 30 hoursBefore this: Calculus, Linear Algebra

What you'll be able to do

  • Solve linear ODEs with constant coefficients and forcing
  • Analyze systems by eigenvalues and phase portraits
  • Use Laplace transforms for discontinuous forcing
  • Judge stability without solving

Start the course

Go through each topic step by step — prose, worked examples, quick checks, and a timed practice round after every section.

Every test ends with a score by topic and a list of what to revisit. Test out of a topic with 80% or better to mark it mastered.

Topics

1.

First-Order Equations

5 lessons

Separable equations and integrating factors

2.

Exact Equations & Substitutions

6 lessons

Exactness tests, integrating factors, Bernoulli and homogeneous types

3.

Second-Order Linear Equations

5 lessons

Characteristic roots: oscillate, decay, or both

4.

The Wronskian & Variation of Parameters

5 lessons

Independence certificates, and the method that handles any forcing

5.

Nonhomogeneous Equations & Resonance

5 lessons

Undetermined coefficients, and what forcing does

6.

Systems of Differential Equations

5 lessons

Eigenvalues run the phase portrait

7.

Nonlinear Systems & Linearization

5 lessons

Jacobians, predator–prey, competition, and the pendulum

8.

Laplace Transforms

5 lessons

Turning calculus into algebra

9.

Laplace II: Steps, Impulses & Convolution

5 lessons

Piecewise forcing, hammer blows, and the convolution theorem

10.

Series Solutions

5 lessons

Power series where formulas fail

11.

Frobenius & Special Functions

5 lessons

Singular points, indicial equations, Bessel and Legendre

12.

Models & Qualitative Behavior

5 lessons

Growth, cooling, mixing, and equilibria

13.

Existence, Uniqueness & Bifurcations

5 lessons

Picard's theorem, phase lines with parameters, harvesting collapse

14.

Boundary Values & Fourier Series

5 lessons

Eigenvalue problems, sine series, the heat and wave equations

15.

Numerical Methods: Euler to Runge–Kutta

5 lessons

Heun, RK4, error orders, and stability ceilings