6. The functions \(f\) and \(g\) are defined by
$$\begin{aligned}
& \mathrm { f } : x \rightarrow 3 x - 4 , \quad x \in \mathbb { R } ,
& \mathrm {~g} : x \rightarrow \frac { 2 } { x + 3 } , \quad x \in \mathbb { R } , \quad x \neq - 3
\end{aligned}$$
- Evaluate fg(1).
- Solve the equation \(\operatorname { gf } ( x ) = 6\).
- Find an expression for \(\mathrm { g } ^ { - 1 } ( x )\).