Answer:
A function f is called decreasing on an interval if f (a) > f (b) whenever a < b and a, b are in the interval.
Explanation:
The domain of the function shown here is the interval [1, 6].On the interval [1, 3], the graph of this function gets higher from left to right; thus we say that this function is increasing on the interval [1, 3].
On the interval [3, 6], the graph of this function gets lower from left to right; thus we say that this function is decreasing on the interval [3, 6].