Let A = {a, b, y} and B = {1, 2, 3, 4}. Find |𝒫(𝒫(A))|.
Sets, relations & functions worksheet with answers
1.Easy
A = {a, b, y}B = {1, 2, 3, 4}
|𝒫(𝒫(A))| =
2.Easy
Let A = {a, c, e, x} and B = {1, 2}. Find |𝒫(A × B)|.
A = {a, c, e, x}B = {1, 2}
|𝒫(A × B)| =
3.Medium
Exactly one region of the Venn diagram is the set (A ∩ C) − (B′ ∩ A). Click its number.
(A ∩ C) − (B′ ∩ A)
- 1region 1
- 2region 2
- 3region 3
- 4region 4
- 5region 5
- 6region 6
- 7region 7
- 8region 8
4.Medium
A survey of 65 people finds that 23 own a laptop (L), 25 a tablet (T) and 41 a smartwatch (W). 7 own L and T, 20 own L and W, 15 own T and W, and 6 own all three. How many are in none of the three sets?
|U| = 65
|(L ∪ T ∪ W)′| =
5.Hard
How many relations on a set with 2 elements are both reflexive and symmetric? Call the number N.
|X| = 2
N =
6.Hard
The arrow diagram shows a function f: A → B with A = {1, 2, 3, 4} and B = {a, b}. Click the description that fits f.
f = {(1, b), (2, b), (3, a), (4, b)}
- 1injective, not surjective
- 2surjective, not injective
- 3bijective
- 4neither
Answer key
- 1. |𝒫(𝒫(A))| = 256
- 2. |𝒫(A × B)| = 256
- 3. region 1
- 4. |(L ∪ T ∪ W)′| = 12
- 5. N = 2
- 6. surjective, not injective
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