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 69b
Textbook Question
Graph each function. ƒ(x) = |x| -3

1
Identify the basic function and transformations: The function ƒ(x) = |x| - 3 is a transformation of the basic absolute value function ƒ(x) = |x|. The transformation involves a vertical shift.
Understand the vertical shift: The '-3' in the function indicates a vertical shift downward by 3 units. This means that every point on the basic absolute value graph, ƒ(x) = |x|, will be moved down 3 units.
Plot the basic absolute value function: Start by plotting the basic graph of ƒ(x) = |x|. This graph has a vertex at (0,0) and forms a 'V' shape, with the left arm descending and the right arm ascending symmetrically from the vertex.
Apply the vertical shift: From the basic graph of ƒ(x) = |x|, shift every point down by 3 units. This will move the vertex from (0,0) to (0,-3).
Draw the transformed graph: After shifting the graph down, redraw the 'V' shaped graph with the new vertex at (0,-3). The arms of the 'V' will still have the same slope as the original absolute value function.

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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Absolute Value Function
The absolute value function, denoted as |x|, measures the distance of a number x from zero on the number line, always yielding a non-negative result. This function has a V-shaped graph that opens upwards, with its vertex at the origin (0,0). Understanding this function is crucial for graphing ƒ(x) = |x| - 3, as it influences the overall shape and position of the graph.
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Vertical Shifts
Vertical shifts occur when a function is adjusted up or down by adding or subtracting a constant from the function's output. In the function ƒ(x) = |x| - 3, the '-3' indicates a downward shift of the entire graph by three units. This concept is essential for accurately positioning the graph of the function relative to the standard absolute value function.
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Graphing Techniques
Graphing techniques involve plotting points and understanding the behavior of functions to create accurate visual representations. For ƒ(x) = |x| - 3, one can start by plotting key points, such as the vertex at (0, -3), and then using the properties of the absolute value function to extend the graph symmetrically. Mastery of these techniques is vital for effectively visualizing and interpreting the function.
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