4 A function f is defined for \(x \in \mathbb { R }\) and is such that \(\mathrm { f } ^ { \prime } ( x ) = 2 x - 6\). The range of the function is given by \(\mathrm { f } ( x ) \geqslant - 4\).
- State the value of \(x\) for which \(\mathrm { f } ( x )\) has a stationary value.
- Find an expression for \(\mathrm { f } ( x )\) in terms of \(x\).