Chapter 7.8, Problem 8P

In Problems 5.1 to 5.9, define each function by the formulas given but on the interval $(-l,l).[\text{Thatis},\text{replace}\pm \pi \text{ by }\pm \text{l and }\pm \pi \text{/2 by }\pm \text{l/2}.]$ Expand each function in a sine-cosine Fourier series and in a complex exponential Fourier series.