Chapter 7.13, Problem 10MP

(a) Sketch at least three periods of the graph of the function represented by the cosine series for $f(x)$ in Problem 9.

(b) Sketch at least three periods of the graph of the exponential Fourier series of period 2 for $f(x)$ in Problem 9.

(c) To what value does the cosine series in (a) converge at $x=0?$ At $x=1?$ At $x=2?$ At $x=-2?$

(d) To what value does the exponential series in (b) converge at $x=0?$ At $x=1?$ At $x=\frac{3}{2}?$ At $x=-2.$