Find the indicated integrals:

$\displaystyle \int x^2\sqrt{3 x + 6}\,dx$ =
$+C$

$\displaystyle \int \frac{4 x + 7}{3 x^2 + 19 x + 6}\,dx$ =
$+C$

$\displaystyle \int \frac{\ln(x)}{x^{5}}\,dx$ =
$+C$