Q. Given the function f(x)=−x2−7x+20, determine the average rate of change of the function over the interval −8≤x≤0.Answer:
Given function: We have the function f(x)=−x2−7x+20. We need to find the average rate of change over the interval [−8,0].To find the average rate of change, we use the formula:Average rate of change = (f(b)−f(a))/(b−a)where a and b are the endpoints of the interval. In this case, a=−8 and b=0.
Find f(a): First, we need to find the value of f(a) where a=−8. Substitute −8 into the function f(x): f(−8)=−(−8)2−7(−8)+20f(−8)=−(64)+56+20f(−8)=−64+56+20f(−8)=−8+20f(−8)=12
Find f(b): Next, we need to find the value of f(b) where b=0. Substitute 0 into the function f(x): f(0)=−(0)2−7(0)+20f(0)=0−0+20f(0)=20
Calculate average rate of change: Now that we have f(a) and f(b), we can calculate the average rate of change.Average rate of change = (f(b)−f(a))/(b−a)Average rate of change = (f(0)−f(−8))/(0−(−8))Average rate of change = (20−12)/(0+8)Average rate of change = 8/8Average rate of change = 1