If , and , , and is the set of real numbers, then find and .

If $f : \mathbb{R} \to \mathbb{R}$, $f(x) = x^3$ and $g : \mathbb{R} \to \mathbb{R}$, $g(x) = 2x^2 + 1$, and $\mathbb{R}$ is the set of real numbers, then find $fog(x)$ and $gof(x)$.