Piecewise functions have different definitions, depending on when you evaluate them.
Given an input x, your function returns:
- 2x if the input is negative
- 1 if the input lies between 0 (included) and 2 (excluded)
- the square root of x if the input is greater than 2 (included)
You want to know what f(0) is. In other words, you want to know what happens if we give 0 as input.
The piecewise definition tells us that, if the input is 0, the function outputs 1.
So, you have f(0) = 1.
1) find the corresponding y values for when x = 0 and when x = 4,
when x = 0, y = 4
when x = 4, y = 4
the coordinates are (0,4) and (4,4)
2) to calculate the average rate of change, find the slope of the two points:
(0,4) (4,4)
(change in y) 4 - 4 = 0
(change in x) 4 - 0 = 4
0/4 = 0
the average rate of change is 0!
Answer: C 20
Explanation: Plug in 2 for k.
2^2 - (2-10) + 4(2) = 20
