(Solved):   Construct the first three Fourier approximations to the square wave function \[ f(x)=\left ...

 

Construct the first three Fourier approximations to the square wave function \[ f(x)=\left\{\begin{array}{ll} -1 & -\pi \leq x<0 \\ 1 & 0 \leq x<\pi \end{array}\right. \] \[ \begin{array}{l} F_{1}(x)= \\ F_{2}(x)= \\ F_{3}(x)= \end{array} \] Using a calculator, graph the function and the first three Fourier approximations to see how the approximation matches the function \( f(x) \).