Given:
The interval is [2,9].
To find:
The average rate of change in f(x) over the interval [2,9].
Solution:
The average rate of change in f(x) over the interval [a,b] is defined as:
[tex]m=\dfrac{f(b)-f(a)}{b-a}[/tex]
In the interval [2,9], the value of a is 2 and the value of b is 9.
Using the above formula, the average rate of change in f(x) over the interval [2,9] is:
[tex]m=\dfrac{f(9)-f(2)}{9-2}[/tex]
[tex]m=\dfrac{f(9)-f(2)}{7}[/tex]
Therefore, the required expression for the average rate of change in f(x) over the interval [2,9] is [tex]\dfrac{f(9)-f(2)}{9-2}[/tex], it is also written is [tex]\dfrac{f(9)-f(2)}{7}[/tex].