What are the steps to find the fourier series of x^2 - 2 in period of -2<x<2? What is [math]f(x)[/math] if [math]ff(x)[/math] or [math]f^2(x) =(x[/math][math]^4+[/math][math]4x^3+3x^2+4x+2[/math][math])^4?[/math]