Let f: [-, R be such that Consider its Fourier series and f() = f(-) and 00 1 zao +(an cos(nx) + b sin(nx)) n=1 with Fourier coefficients do, a1,... and b,b2,... given by Show that 1 A = - 7 b = 1 71 f(x) cos(nx) dx -TL f(x) sin(nx) dx -TL E L |f(x)/ dx