Remember that the average rate of change of a function over an interval is the slope of the straight line connecting the end points of the interval. To find those slopes, we are going to use the slope formula:
![m= \frac{y_{2}-y_{1}}{x_2-x_1}](https://tex.z-dn.net/?f=m%3D%20%5Cfrac%7By_%7B2%7D-y_%7B1%7D%7D%7Bx_2-x_1%7D%20)
Rate of change of
![a](https://tex.z-dn.net/?f=a)
:
From the graph we can infer that the end points are (0,1) and (2,4). So lets use our slope formula to find the rate of change of
![a](https://tex.z-dn.net/?f=a)
:
![m= \frac{y_{2}-y_{1}}{x_2-x_1}](https://tex.z-dn.net/?f=m%3D%20%5Cfrac%7By_%7B2%7D-y_%7B1%7D%7D%7Bx_2-x_1%7D%20)
![m= \frac{4-1}{2-0}](https://tex.z-dn.net/?f=m%3D%20%5Cfrac%7B4-1%7D%7B2-0%7D%20)
![m= \frac{3}{2}](https://tex.z-dn.net/?f=m%3D%20%5Cfrac%7B3%7D%7B2%7D%20)
![m=1.5](https://tex.z-dn.net/?f=m%3D1.5)
The average rate of change of the function
![a](https://tex.z-dn.net/?f=a)
over the interval [0,2] is 1.5
Rate of change of
![b](https://tex.z-dn.net/?f=b)
:
Here the end points are (0,0) and (2,2)
![m= \frac{2-0}{2-0}](https://tex.z-dn.net/?f=m%3D%20%5Cfrac%7B2-0%7D%7B2-0%7D)
![m= \frac{2}{2}](https://tex.z-dn.net/?f=m%3D%20%5Cfrac%7B2%7D%7B2%7D%20)
![m=1](https://tex.z-dn.net/?f=m%3D1)
The average rate of change of the function
![b](https://tex.z-dn.net/?f=b)
over the interval [0,2] is 1
Rate of change of
![c](https://tex.z-dn.net/?f=c)
:
Here the end points are (0,-1) and (2,0)
![m= \frac{0-(-1)}{2-0}](https://tex.z-dn.net/?f=m%3D%20%5Cfrac%7B0-%28-1%29%7D%7B2-0%7D)
![m= \frac{1}{2}](https://tex.z-dn.net/?f=m%3D%20%5Cfrac%7B1%7D%7B2%7D%20)
![m=0.5](https://tex.z-dn.net/?f=m%3D0.5)
The average rate of change of the function
![c](https://tex.z-dn.net/?f=c)
over the interval [0,2] is 0.5
Rate of change of
![d](https://tex.z-dn.net/?f=d)
:
Here the end points are (0,0.5) and (2,2.5)
![m= \frac{2.5-0.5}{2-0}](https://tex.z-dn.net/?f=m%3D%20%5Cfrac%7B2.5-0.5%7D%7B2-0%7D%20)
![m= \frac{2}{2}](https://tex.z-dn.net/?f=m%3D%20%5Cfrac%7B2%7D%7B2%7D%20)
![m=1](https://tex.z-dn.net/?f=m%3D1)
The average rate of change of the function
![d](https://tex.z-dn.net/?f=d)
over the interval [0,2] is 1
We can conclude that the <span>function that has the greatest rate of change over the interval [0, 2] is
the function a.</span>