\[\boxed{\mathbf{816}\mathbf{.}}\]
\[1)\ g(x) = 1 - x\ \ и\ \ f(g) = g^{\frac{3}{2}}:\]
\[f\left( g(x) \right) = (1 - x)^{\frac{3}{2}} = \sqrt{(1 - x)^{3}}.\]
\[2)\ g(x) = \ln x\ и\ \ f(g) = \sqrt{g}:\]
\[f\left( g(x) \right) = \sqrt{\ln x}.\]