Can a function be considered odd or even if has a discontinuity?

Solution 1:

A function $f$ is odd if whenever both $x$ and $-x$ are in its domain $$ f(x) = -f(-x). $$

We don't usually include the italicized part of the previous definition since it's not usually an issue.

The formal definition of a function requires specifying its domain. Think about the domains of the functions you are trying to define with your formulas.