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Moira uses a difference quotient to determine the average rate of change of f(x) = x² + 14x from x = –11 to x = 8. She shows the following work.

Determine f(x + h).

User IslamTaha
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Final answer:

To determine the average rate of change of the function f(x) = x² + 14x from x = –11 to x = 8, use the difference quotient by finding f(x + h) and f(x), then dividing the difference by the change in x (h). The average rate of change is calculated as 11 units.

Step-by-step explanation:

To determine the average rate of change of the function f(x) = x² + 14x from x = –11 to x = 8, you can use the difference quotient formula which is given by f(x + h) – f(x) divided by h, where h is the change in the value of x. In Moira's case, h would be the difference between the two x-values: 8 - (-11) = 19. You would plug in x and x + h into the original function to find the values of f(x) and f(x + h) respectively.

To find f(x + h), first replace x with x + h in the equation and simplify:

f(x + h) = (x + h)^2 + 14(x + h)

Then, Moira can calculate the difference quotient to find the average rate of change:

f(8) = 8² + 14*8 = 64 + 112 = 17

Thus, the average rate of change of the function from x = –11 to x = 8 is 11 units.

User Deepak Gupta
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