Part 1: Graph piecewise functions from tables and equations.

Isabel sells new and used mystery novels online. Her customers are primarily in the United States. She sends up to 10 pounds of books in one shipment. She uses the United States Postal Service’s Media Mail service because it is inexpensive for her customers. Current Media Mail shipping prices for book shipments weighing 10 pounds or less appear below.

Weight Not Over (lbs.)

Price

0

$0

1

$2.69

2

$3.17

3

$3.65

4

$4.13

5

$4.61

6

$5.09

7

$5.57

8

$6.03

9

$6.49

10

$6.95

1 answer

To graph the piecewise function representing Isabel's shipping costs based on the weight of the books, we will first create a table from the provided data and then establish the piecewise function based on this data.

Table of Shipping Prices

| Weight Not Over (lbs.) | Price ($) | |------------------------|-----------| | 0 | 0 | | 1 | 2.69 | | 2 | 3.17 | | 3 | 3.65 | | 4 | 4.13 | | 5 | 4.61 | | 6 | 5.09 | | 7 | 5.57 | | 8 | 6.03 | | 9 | 6.49 | | 10 | 6.95 |

Piecewise Function

The piecewise function \( f(x) \) that describes the shipping price based on weight can be defined as follows:

\[ f(x) = \begin{cases} 0 & \text{if } 0 \leq x < 1 \ 2.69 & \text{if } 1 \leq x < 2 \ 3.17 & \text{if } 2 \leq x < 3 \ 3.65 & \text{if } 3 \leq x < 4 \ 4.13 & \text{if } 4 \leq x < 5 \ 4.61 & \text{if } 5 \leq x < 6 \ 5.09 & \text{if } 6 \leq x < 7 \ 5.57 & \text{if } 7 \leq x < 8 \ 6.03 & \text{if } 8 \leq x < 9 \ 6.49 & \text{if } 9 \leq x < 10 \ 6.95 & \text{if } x = 10 \end{cases} \]

Graphing the Function

To graph the piecewise function:

  1. Plot the Points: Start by plotting the points from the table onto the coordinate system. The x-axis will represent the weight (in pounds), and the y-axis will represent the price (in dollars).

  2. Draw the Segments: Connect the points with horizontal line segments (noting that they are not included for the open intervals at the end of each segment). The points at \( x = 0 \), \( x = 1 \), \( x = 2 \), ... up to \( x = 10 \) will be solid dots since they have defined prices.

  3. Label the Axes: Make sure to label the x-axis as "Weight (lbs.)" and the y-axis as "Price ($)".

The graph will show a step function that increases as the weight increases, reflecting the discrete pricing structure of the shipping costs.

If you would like, I can help with additional details or any specific part of the graphing process!