Compilers Questions and Answers for Freshers on “Relations”.
1. If A ∩ B = B, then?
a) A ⊂ B
b) A = ø
c) B ⊂ A
d) B = ø
Answer: c
Clarification: Since A ∩ B = B, hence B ⊂ A.
2. Empty set is a _____________
a) Invalid set
b) Infinite set
c) Finite set
d) None of the mentioned
Answer: c
Clarification: Empty set is a finite set.
3. If A, B and C are any three sets, then A – (B ∪ C) is equal to _____________
a) (A – B) ∪ (A – C)
b) (A – B) ∪ C
c) (A – B) ∩ (A – C)
d) (A – B) ∩ C
Answer: c
Clarification: it is De’ Morgan law.
4. A = {x: x ≠ x} represents?
a) {0]
b) {1}
c) {}
d) {x}
Answer: c
Clarification: That is a fact.
5. If A, B, C be three sets such that A ∪ B = A ∪ C and A ∩ B = A ∩ C, then?
a) A=B
b) A=C
c) B=C
d) A=B=C
Answer: c
Clarification: Transition Law.
6. The number of proper subsets of the set {1, 2, and 3} is?
a) 8
b) 6
c) 7
d) 5
Answer: b
Clarification: Number of proper subsets of the set {1, 2, 3) = 23 – 2 = 6.
7. If A and B are any two sets, then A ∪ (A ∩ B) is equal to _____________
a) A
b) B
c) A^C
d) B^C
Answer: a
Clarification: A ∩ B ⊆ A Hence A ∪ (A ∩ B) = A.
8. If A, B and C are any three sets, then A × (B ∪ C) is equal to _____________
a) (A × B) ∪ (A × C)
b) (A × B) ∩ (A × C)
c) (A ∪ B) × (A ∪ C)
d) None of the mentioned
Answer: a
Clarification: It is distributive law.