If f(x)=∑n=1∞sin(nx)n2f(x) = \sum_{n=1}^{\infty} \frac{\sin(nx)}{n^2}f(x)=∑n=1∞n2sin(nx), what can be concluded about f(x)f(x)f(x)?
Continuous everywhere
Differentiable everywhere
Discontinuous at x=0x=0x=0
Nowhere continuous