9 You are given that
\(\mathrm { f } ( x ) = 2 x + 3 \quad\) for \(x < 0 \quad\) and
\(\mathrm { g } ( x ) = x ^ { 2 } - 2 x + 1\) for \(x > 1\).
- Find \(\mathrm { gf } ( x )\), stating the domain.
- State the range of \(\mathrm { gf } ( x )\).
- Find (gf) \({ } ^ { - 1 } ( x )\).