The Venn diagram shows every element of the universal set U and of the sets A and B. Find |(B ∩ A)′|, the number of elements of (B ∩ A)′.
Sets, relations & functions worksheet with answers
1.Easy
A = {7, 8, 15, 16, 17, 18, 20}B = {10, 15, 16, 18, 20}|U| = 9
|(B ∩ A)′| =
2.Easy
Exactly one region of the Venn diagram is the set (A′ ∩ B) ∩ (B − A). Click its number.
(A′ ∩ B) ∩ (B − A)
- 1region 1
- 2region 2
- 3region 3
- 4region 4
3.Medium
The relation R on {1, 2, 3, 4} is drawn as a directed graph (a loop means (x, x) ∈ R). Exactly one of the four properties holds. Click it.
R = {(1, 1), (2, 1), (2, 2), (3, 2), (4, 3)}
- 1reflexive
- 2symmetric
- 3antisymmetric
- 4transitive
4.Medium
Each number in the Venn diagram is the number of elements in that region. Find |(B ∪ A′) − (A − C)|.
|U| = 48
|(B ∪ A′) − (A − C)| =
5.Hard
The functions f and g on {1, 2, 3, 4, 5} are given by their tables. Find (f ∘ f)(1).
f: 1 ↦ 3, 2 ↦ 4, 3 ↦ 2, 4 ↦ 4, 5 ↦ 5g: 1 ↦ 5, 2 ↦ 3, 3 ↦ 2, 4 ↦ 5, 5 ↦ 2
(f ∘ f)(1) =
6.Hard
The functions f and g on {1, 2, 3, 4, 5} are given by their tables. Find (f ∘ g)(5).
f: 1 ↦ 2, 2 ↦ 4, 3 ↦ 4, 4 ↦ 1, 5 ↦ 5g: 1 ↦ 4, 2 ↦ 1, 3 ↦ 1, 4 ↦ 3, 5 ↦ 5
(f ∘ g)(5) =
Answer key
- 1. |(B ∩ A)′| = 5
- 2. region 4
- 3. antisymmetric
- 4. |(B ∪ A′) − (A − C)| = 34
- 5. (f ∘ f)(1) = 2
- 6. (f ∘ g)(5) = 5
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