Let \(f\text{ }:\text{ }{R}_{+}\text{ }\to \text{ }\left[5,\text{ }\infty \right)\) be defined as \(f\left(x\right)=9{x}…

Let \(f\text{ }:\text{ }{R}_{+}\text{ }\to \text{ }\left[5,\text{ }\infty \right)\) be defined as \(f\left(x\right)=9{x}^{2}+6x-5,\) where \({R}_{+}\) is the set of all non-negative real numbers. Then, \(f\) is