The signal f(t) of period 8 is defined by:
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a) Using Excel, or otherwise, plot a graph of the signal f(t).
b) Determine the first four terms of the Fourier series for 1(t).
c) On the same axes plot the signal 1 (t) and the sum of the first four terms of the Fourier series. Comment briefly on the convergence of the Fourier series.
d) Express the Fourier series for 1(0 in general terms using Σ notation.