1. **Problem Statement:**
We have a piecewise function describing the distance $f(x)$ in kilometers Michelle and Rashid travel after $x$ hours of biking:
$$
f(x) = \begin{cases} 16x & 0 \leq x \leq 1 \\ 10(x - 1) + 16 & 1 < x \leq 2 \\ 14(x - 2) + 26 & 2 < x \leq 3 \\ 12(x - 3) + 40 & 3 < x \leq 4 \end{cases}
$$
We will answer the following:
- When are they going fastest and slowest?
- What is the domain of $f(x)$?
- Find $f(2)$ and interpret it.
- Find $f(3)$ and interpret it.
- Find the total distance traveled.
2. **Finding the speeds (rates) in each interval:**
Speed is the rate of change of distance with respect to time, i.e., the slope of each piece.
- For $0 \leq x \leq 1$, $f(x) = 16x$, speed = 16 km/h.
- For $1 < x \leq 2$, $f(x) = 10(x-1) + 16 = 10x + 6$, speed = 10 km/h.
- For $2 < x \leq 3$, $f(x) = 14(x-2) + 26 = 14x - 2$, speed = 14 km/h.
- For $3 < x \leq 4$, $f(x) = 12(x-3) + 40 = 12x + 4$, speed = 12 km/h.
3. **Fastest and slowest parts:**
- Fastest speed is $16$ km/h during $0 \leq x \leq 1$ hour.
- Slowest speed is $10$ km/h during $1 < x \leq 2$ hours.
4. **Domain of $f(x)$:**
The function is defined for $x$ from 0 to 4 hours, so the domain is:
$$0 \leq x \leq 4$$
5. **Find $f(2)$:**
Since $2$ is in the interval $1 < x \leq 2$, use the second piece:
$$f(2) = 10(2 - 1) + 16 = 10(1) + 16 = 26$$
This means after 2 hours, they have traveled 26 kilometers.
6. **Find $f(3)$:**
Since $3$ is in $2 < x \leq 3$, use the third piece:
$$f(3) = 14(3 - 2) + 26 = 14(1) + 26 = 40$$
After 3 hours, they have traveled 40 kilometers.
7. **Total distance traveled:**
At $x=4$ (end of ride), use the last piece:
$$f(4) = 12(4 - 3) + 40 = 12(1) + 40 = 52$$
So, total distance traveled is 52 kilometers.
**Summary:**
- Fastest: first hour at 16 km/h.
- Slowest: second hour at 10 km/h.
- Domain: $0 \leq x \leq 4$.
- $f(2) = 26$ km means distance after 2 hours.
- $f(3) = 40$ km means distance after 3 hours.
- Total distance $f(4) = 52$ km.
Piecewise Bike 977625
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