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Ch. R - Algebra Review
Lial - Trigonometry 12th Edition
Lial12th EditionTrigonometryISBN: 9780136552161Not the one you use?Change textbook
Chapter 1, Problem 19

List the elements in each set. See Example 1. {p|p is a number whose absolute value is 4}

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1
Understand the problem: We need to find all numbers \( p \) such that the absolute value of \( p \) is 4. The absolute value of a number is its distance from zero on the number line, regardless of direction.
Recall the definition of absolute value: For any number \( p \), \( |p| = 4 \) means \( p \) can be either 4 or -4 because both have an absolute value of 4.
Write the equation representing the condition: \( |p| = 4 \). This implies two possible equations: \( p = 4 \) or \( p = -4 \).
List the elements of the set by including all values of \( p \) that satisfy the condition: \( \{4, -4\} \).
Verify the solution by checking the absolute value of each element: \( |4| = 4 \) and \( |-4| = 4 \), confirming both satisfy the condition.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Absolute Value

The absolute value of a number is its distance from zero on the number line, regardless of direction. It is always non-negative. For example, the absolute value of both 4 and -4 is 4, denoted as |4| = 4 and |-4| = 4.
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Set Notation and Description

Set notation describes a collection of elements that satisfy a specific property. In this question, the set is defined by a condition on its elements, such as all numbers p where |p| = 4. Understanding how to interpret and list elements from such descriptions is essential.
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Solving Absolute Value Equations

To find elements satisfying an absolute value equation like |p| = 4, solve for p by considering both positive and negative cases: p = 4 and p = -4. This approach helps identify all possible elements in the set.
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