What does Navier–Stokes actually say—and what does the OpenAI announcement claim? Decode every term, verify exact fluid solutions, calculate energy decay, and test your understanding with 12 worked practice problems.
Fourier series reveal how complex periodic signals can be rebuilt from simple sine and cosine waves. Learn how harmonics, Fourier coefficients, orthogonality, partial sums, and frequency-domain thinking connect to sound, heat flow, PDEs, engineering, and quantum mechanics.