## Precalculus (6th Edition)

The graph of $f(x) = \sqrt{x}$ is the one in Option $D$. The domain is $[0, +\infty)$.
The graph of the square root function $f(x) = \sqrt{x}$ is a curve (half parabola) that opens to the right (refer to age 251 of the textbook). The values of the function are greater than or equal to zero. Thus, the graph of $f(x) = \sqrt{x}$ is the one in Option $D$. The allowed values of $x$ are from $0$ to the right so its domain is $[0, +\infty)$.