6. (Fourier series) Find the Fourier coefficients an and bn of following functions when f(x) can be expressed in a Fourier series as, f(x) = ao + n=1 an cos(nx) + bn sin(nx). For each function, in a single plot, plot the function and the Fourier series taking upto n = 1, 5, 10, and, 50 terms using MATLAB in the given limit. Comment if it fails to converge on some values of x in the limit. (a) f(x)=x in