To find the reflection of the solid graph represented by the function \( f(x) = x^3 + 1 \), we first note that a reflection across the x-axis involves negating the entire function.
Thus, the reflected function \( g(x) \) will be:
\[ g(x) = -f(x) = -(x^3 + 1) = -x^3 - 1 \]
Now, looking at the provided options, we see that:
- Option #1: \( g(x) = -x^2 + 1 \) (not a cubic function)
- Option #2: \( g(x) = -x^3 - 1 \) (this is our equation)
- Option #3: \( g(x) = -x^3 + 1 \) (does not match)
- Option #4: \( g(x) = x^3 - 1 \) (does not match)
Therefore, the correct choice for the equation of the dotted graph is:
Option #2.