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

Key Concepts

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.

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.

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.