Table of contents
- 0. Review of Algebra4h 16m
- 1. Equations & Inequalities3h 18m
- 2. Graphs of Equations43m
- 3. Functions2h 17m
- 4. Polynomial Functions1h 44m
- 5. Rational Functions1h 23m
- 6. Exponential & Logarithmic Functions2h 28m
- 7. Systems of Equations & Matrices4h 6m
- 8. Conic Sections2h 23m
- 9. Sequences, Series, & Induction1h 19m
- 10. Combinatorics & Probability1h 45m
3. Functions
Intro to Functions & Their Graphs
Problem 153
Textbook Question
Find the given distances between points P, Q, R, and S on a number line, with coordi-nates -4, -1, 8, and 12, respectively. d(Q,R)
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1
Identify the coordinates of points Q and R. Point Q is at -1 and point R is at 8.
Use the distance formula for points on a number line, which is the absolute value of the difference between the coordinates of the two points. The formula is |x_2 - x_1|.
Substitute the coordinates of points Q and R into the distance formula. So, substitute -1 for x_1 (Q's coordinate) and 8 for x_2 (R's coordinate).
Calculate the difference 8 - (-1). Remember to account for the negative sign in front of 1.
Take the absolute value of the result from the previous step to find the distance d(Q, R).
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Distance on a Number Line
The distance between two points on a number line is calculated using the absolute difference of their coordinates. For points A and B with coordinates a and b, the distance d(A, B) is given by |a - b|. This concept is fundamental in understanding how to measure the separation between any two points in a one-dimensional space.
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Absolute Value
Absolute value is a mathematical function that measures the distance of a number from zero on the number line, regardless of direction. It is denoted as |x|, where x is any real number. This concept is crucial when calculating distances, as it ensures that the result is always non-negative, reflecting the actual distance between points.
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Coordinate System
A coordinate system provides a framework for identifying the position of points in space using numbers. In a one-dimensional number line, each point is represented by a single coordinate. Understanding how to interpret these coordinates is essential for solving problems related to distances, as it allows for the correct identification of points involved in the calculation.
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