Answer
The function $ f $ is decreasing in the interval $\underline{\left( 0,2 \right)}$
Work Step by Step
We know that if the values of y decrease when values of x increase then the function is said to be decreasing.
In mathematical terms, the function is decreasing if
$ f\left( {{x}_{2}} \right){{x}_{1}}$
And the function is said to be decreasing in a particular interval, when the graph is going down in that interval.
In the provided graph, it is decreasing during the interval $\left( 0,2 \right)$.
Thus, the function $ f $ is decreasing on the interval $\underline{\left( 0,2 \right)}$.