Hello Everyone! Today we are asked to find an an approximation for f(x) that gives a finite sum values for all x where f(x) is defined as

. I don't know if I rephrased it right, but the exact problem goes like this:

"

*What does the statement* *mean? Can you write down a ﬁnite sum approximation of f(x)?*"

Since this one resembles a fourier sine series, my first guess is to find the exact function,f(x), such that

But from there I'm lost as to how I would find f(x). Anyone got any idea to find f(x) or at least find an approximation of it? Thanks everyone in advance!