Question

Given the function f(x) = –22 – 7x + 18, determine the average rate of change

of the function over the interval -10 < x < -1.

Answer 1

Note: May be you meant to write the function as:

f(x)=-22x²-7x+18

Answer:

The Average rate of function = 235

Explanation:

Given the function

f(x) = –22x² – 7x + 18

Interval = -10 < x < -1

so

taking x₁ = -9, x₂ = -2 in the interval

f(x₁) = f(-9) = -22(-9)² – 7(-9) + 18

= -1701

f(x₂) = f(-2) = -22(-2)² – 7(-2) + 18

= -56

Using the formula

Average rate of change = f(x₂) - f(x₁) / x₂-x₁

= (-56) - (-1701) / (-2) - (-9)

= (-56 + 1701) / (-2+9)

= 1645 / 7

= 235

Thus, the Average rate of function = 235