Correct. In a quadratic function, there are no variables in a denominator or radical expressions, so nothing will restrict the domain. This is why the domain is all real numbers. Because the coefficient of $\displaystyle{{x}}^{{2}}\usepackage{cmbright}\Huge\$ is positive, the graph of the function will open upward. Graph the function to find the vertex, $\displaystyle{\left({2},-{4}\right)}\usepackage{cmbright}\Huge\$ . The y-value is the minimum and will determine the range. The range is $\displaystyle{f{{\left({x}\right)}}}\ge-{4}\usepackage{cmbright}\Huge\$ .