A Fourier series expansion of a step function is possible, but diverges when applied to infinite step functions, while finite step functions yield valid results. To compute the Fourier series, one can separate the function into constant segments and calculate the integrals for each part, then sum them. An alternative method involves calculating the Fourier series normally and applying a factor to modify the function's behavior, though this may also lead to divergence for many frequencies. The discussion includes a desire to extract a mathematical function from a voltage response graph, suggesting a piecewise definition may be more effective than other methods. Overall, the feasibility of Fourier series for step functions depends on their finiteness and the approach taken.
