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Ch. R - Review of Basic Concepts
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063Not the one you use?Change textbook
Chapter 1, Problem 43

Determine whether each statement is true or false. 9 ∉ {8, 5, 2, 1}

Verified step by step guidance
1
Understand the notation: The symbol \( \in \) means "is an element of," and \( \notin \) means "is not an element of."
Identify the set given: \( \{8, 5, 2, 1\} \) is a set containing the elements 8, 5, 2, and 1.
Check if the number 9 is in the set: Look through the elements of the set to see if 9 appears.
Since 9 does not appear in the set \( \{8, 5, 2, 1\} \), the statement \( 9 \notin \{8, 5, 2, 1\} \) is true.
Therefore, the statement correctly expresses that 9 is not an element of the set.

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Key Concepts

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

Set Membership

Set membership refers to whether an element belongs to a given set. The symbol ∈ denotes 'is an element of,' while ∉ means 'is not an element of.' Understanding this helps determine if a specific number is included in the set.
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Interval Notation

Set Notation

Set notation uses curly braces {} to list elements of a set. Each element inside the braces is a member of the set. Recognizing this notation is essential to identify which numbers are included in the set.
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True or False Statements

Evaluating true or false statements involves verifying the accuracy of a claim based on given information. In this context, it means checking if the element 9 is or is not in the set {8, 5, 2, 1} to determine the statement's truth value.
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