Individual #analysis.infinitesimal_calculus__analysi  a branch of mathematics involving calculus and the theory of limits; sequences and series and integration and differentiation
  >part of:  #infinitesimal_calculus__calculus__the_calculus  the branch of mathematics that is concerned with limits and with the differentiation and integration of functions
  >part:  #Fourier_analysis__harmonic_analysis  analysis of a periodic function into a sum of simple sinusoidal components

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