## Elementary Algebra

When the question asks for the domain of the function, it is asking for what values of x can be legally substituted into the function. (For instance, in the function $\frac{2}{x}$, x $\ne$ 0, for this would make the denominator of the fraction equal to 0.) In the given function, any real number can be substituted for the variable $x$. Thus, the domain of the function is the set of all real numbers.