Final answer:
To determine the sum of the Fourier series of a function on a given interval, we need to compute the Fourier coefficients, which is not required in this problem. Instead, we can understand the concept of the Fourier series and its representation of periodic functions.
Step-by-step explanation:
The question asks to determine the sum of the Fourier series of a function on a given interval without computing the Fourier coefficients. The Fourier series represents a periodic function as an infinite sum of sine and cosine functions. To find the sum of the series, we need to know the coefficients, which can be computed using certain formulas. However, since we are not required to compute the coefficients in this problem, we can't determine the exact sum of the Fourier series. Instead, we can understand the concept of the Fourier series and its representation of periodic functions.