Relations and Functions  MCQs

MCQs of Relations and Functions

Showing 21 to 30 out of 145 Questions
21.
f : [-π2, π2]  [-1, 1] is a bijection if _____
(a) f(x) = x
(b) f(x) = sinx
(c) f(x) = x2
(d) f(x) = cosx
Answer:

Option (b)

22.
f : R  R, f(x) = x2 + 2x + 3 is _____
(a) a bijection
(b) one-one but not onto
(c) onto but not one-one
(d) many-one and not onto
Answer:

Option (d)

23.

If a ∗ b = ab + 1  on R, is _____

(a) commutative, but not associative
(b) associative, but not commutative
(c) neither commutative nor associative
(d) both commutative and associative
Answer:

Option (a)

24.

If a ∗ b = a+ b2 on Z, then ∗ is _____

(a) commutative and associative
(b) commutative and not associative
(c) not commutative and associative
(d) nethier commutative nor associative
Answer:

Option (b)

25.
If a  b = a + b - ab on Q -{1}, then the identity and the inverse of a for are respectively _____
(a) 0 and aa -1 
(b) 1 and a - 1a
(c) -1 and a
(d) 0, 1a
Answer:

Option (a)

26.
If a  b = ab3 on Q+, then 3  (15  12) is _____
(a)  5160
(b)  130
(c)  3160
(d)  360
Answer:

Option (b)

27.

If  is defined on P(X) (X ) by, A  B = (A  B) - (A  B), then _____

(a)

Identity for Δ is ø and inverse of A is A

(b)

Identity for Δ is A and inverse of A is ø

(c)

Identity for Δ is A' and inverse of A is A

(d)

Identity for Δ is X and inverse of A is ø

Answer:

Option (a)

28.

S is defined on N × N by ((a, b), (c, d)) ∈ S ⇔ a + d = b + c _____

(a) S is reflexive, but not symmetric
(b) S is Reflexive and transitive only
(c) S is an equivalence relation
(d) S is Transitive only
Answer:

Option (c)

29.
Let S be the relation on the set A = {5, 6, 7, 8}, S = {(5, 6), (6, 6), (5, 5), (8, 8), (5, 7), (7, 7), (7, 6)}, then _____
(a) S is reflexive and symmetric but not transitive
(b) S is reflexive and transitive but not Symmetric
(c) S is symmetric and transitive but not reflexive
(d) S is an equivalence relation.
Answer:

Option (b)

30.
If f : R+  R, f(x) = xx + 1 is _____
(a) one-one and onto
(b) one-one and not onto
(c) not one-one and not onto
(d) onto but not one-one
Answer:

Option (b)

Showing 21 to 30 out of 145 Questions