How many subsets of A = {1, 2, 3, 4, 5} contain neither 4 nor 5? Call the number N.
Sets, relations & functions worksheet with answers
The Venn diagram shows every element of the universal set U and of the sets A and B. Find |A ∩ B|, the number of elements of A ∩ B.
R = {(1, 3), (2, 1), (2, 4), (3, 1), (4, 1), (4, 4)} is a relation on {1, 2, 3, 4}. What is the smallest number k of ordered pairs that must be added to R to make it transitive (the size of the transitive closure minus |R|)?
Of 64 first-year students, 17 passed Mathematics (M), 31 passed Physics (P) and 35 passed Chemistry (C). 6 passed M and P, 9 passed M and C, 19 passed P and C, and 5 passed all three. How many are in M only?
The arrow diagram shows a function f: A → B with A = {1, 2, 3, 4} and B = {a, b, c, d}. Click the description that fits f.
- 1injective, not surjective
- 2surjective, not injective
- 3bijective
- 4neither
The bijection f on {1, 2, 3, 4, 5} is given by its table. Find f−1(1).
Answer key
- 1. N = 8
- 2. |A ∩ B| = 3
- 3. k = 4
- 4. |M − (P ∪ C)| = 7
- 5. bijective
- 6. f−1(1) = 3
Full step-by-step solutions: practise this topic on examproblems.com.