Exercise · ZW-SET-MEMBERSHIP-008 · ★★☆ Intermediate
Let \(B = \{1, \{1\}, \{\{1\}\}\}\). How many elements does B have?
Choose one option.
Show answer
- B. 3
Explanation
The elements are 1, \(\{1\}\) and \(\{\{1\}\}\), three distinct objects. Confusing 1 with \(\{1\}\) leads to counting two.
Review the concept: Set membership
The relation stating that an object \(x\) is one of the elements of a set \(A\), symbolized by \(\in\).
\[x \in A\]
More practice problems: set membership
- ZW-SET-MEMBERSHIP-001 What does x ∈ A mean?
- ZW-SET-MEMBERSHIP-002 What is the negation of x ∈ A?
- ZW-SET-MEMBERSHIP-003 Let A = \1, 2, 3\. Which statement is true?
- ZW-SET-MEMBERSHIP-004 Let A = \∅, \1\\. Which statement is true?
- ZW-SET-MEMBERSHIP-005 Can a set contain the same element twice?
- ZW-SET-MEMBERSHIP-006 Which symbol expresses that x does not belong to A?
- ZW-SET-MEMBERSHIP-007 Let A = \∅, \∅\\. Which statement is true?
- ZW-SET-MEMBERSHIP-009 Let C = \\1\, \2\, \3\\. Which statement is true?