(4). If we break down this piecewise function, we have 3 main expressions to deal with, 'h(x) = 5 if {x ≥ 4}' (represented by the green graph) 'h(x) = x if {0 ≤ x ≤ 4}' (represented by the blue graph) and 'h(x) = 1 / 2x + 2 if {x < 0}' (represented by the red graph).
Take a look at the attachment below for your graph of these 3 functions / expressions.
(5). For this part we want to determine the average rate of change of the function f(x) = 4x² - 5x - 8 over the interval [- 2,3]. Remember that to calculate average rate of change between the 2 points we use the following formula...
f(b) - f(a) / b - a,
f(3) = 4(3)² - 5(3) - 8 = 4(9) - 15 - 8 = 36 - 15 - 8 = 13,
f(- 2) = 4(- 2)² - 5(- 2) - 8 = 4(4) + 10 - 8 = 16 + 10 - 8 = 18
13 - 18 / 3 - (- 2) = - 5 / 5 = - 1
Therefore the average rate of change of the function f(x) = 4x² - 5x - 8 over the interval [- 2,3] will be - 1.
Do you have a diagram i can see?
First we need to find f(2) and f(5), which are 5 and 11 respectively; all you have to do is plug in 2 and 5.
Then, we use the following formula:
(f(b)-f(a))/(b-a),
where b and a are the largest and smallest x values respectively.
Finally, we plug our values in:
(11-5)/(5-2)=6/3=2
In fact, the average rate of change of any linear function is just the coefficient of the x term. Hope this helped!