Not necessarily. There are series over all kinds of subsets and supersets of the set of real numbers.
Chat with our AI personalities
sequence
a function whose range is in the real number
It could be a subset: for example, for the function y = log(x), the domain is x > 0. There are many functions whose domain is the complex plane.
It is a trigonometric function whose argument is the number theta.
A function is a relation whose mapping is a bijection.