section_path: Series of functions/Trigonometric series
section_name: Trigonometric series
paragraph_text: Trigonometric series
  
  A series of functions in which the terms are trigonometric functions is called a trigonometric series:
  
  1 2 A 0 + ∑ n = 1 ∞ (A n cos n x + B n sin n x). {\displaystyle {\frac {1}{2}}A_{0}+\sum _{n=1}^{\infty }\left(A_{n}\cos nx+B_{n}\sin nx\right).}
  
  The most important example of a trigonometric series is the Fourier series of a function.