## Elementary and Intermediate Algebra: Concepts & Applications (6th Edition)

$g+h$ and $g\cdot h$ both have $\mathbb{R}$ as their domain.
The domain of $g+h$ is the intersection of domains of g and of h. The domain of $g\cdot h$ is the intersection of domains of g and of h. Both g and h are defined on $\mathbb{R}$ so, $g+h$ and $g\cdot h$ both have $\mathbb{R}$ as their domain.