Answer:
3
Step-by-step explanation:
The average rate of change is
f(x2) - f(x1)
-----------------
x2-x1
We want to find the change from 1 to 3
f(3) = 8
f(1) = 2
f(3) - f(1) 8-2 6
----------------- = ------------ = ---- = 3
3-1 2 2