2.6.2.31 Trigonometric Fourier series
condition: Calculate the sum of coefficients \( a_{6}+b_{6} \) of the Fourier series expansion of the function \[ f(x)=\left\{\begin{array}{cl} 3+x, & x \in[-3 ; 0] \\ 7, & x \in(0 ; 3] \end{array}\right. \]
Trigonometric Fourier series - calculation of Fourier coefficients, expansion of functions in cosines and sines, plotting graphs of the sum of the Fourier series using the Dirichlet theorem, as well as graphs of partial sums.