A Fourier series is an expansion of a periodic function in terms of an infinite sum of sines and cosines.
Dini's test | Dirichlet Fourier series conditions | Fourier-Bessel series | Fourier cosine series | Fourier-Legendre series | Fourier sine series | Fourier transform | generalized Fourier series | Gibbs phenomenon | harmonic addition theorem | harmonic analysis | lacunary Fourier series | Lebesgue constants | power spectrum | Riesz-Fischer theorem | simple harmonic motion
college level