Relations and Functions  MCQs

MCQs of Relations and Functions

Showing 81 to 90 out of 145 Questions
81.
f : Z  Z × {0, 1}, f(n)= n2, 0,n is evenn - 12, 1,n is odd,  then _____.
(a) f-1 does not exist
(b) f-1((n, 0)) = 2n + 1, f-1((n, 1)) = 2n
(c) f-1((n, 0)) = n2, f-1((n + 1)) = 2n - 1
(d) f -1((n, 0)) = 2n, f -1((n, 1)) = 2n + 1
Answer:

Option (d)

82.
If f : R → R, f(x) = [ x ], then f -1 _____.
(a) does not exist
(b) = f
(c) x
(d) = ⌈ x ⌉
Answer:

Option (a)

83.
If f : R → Z, f(x) = x , then f -1does not exist, because_____.
(a) f is not one - one, f is not onto
(b) f is one - one, f is not onto
(c) f is not one - one, f is onto
(d) f is one - one, f is onto
Answer:

Option (c)

84.
If f : N × N → N × N, f((m, n)) = (n, m) , then _____.
(a) f -1 does not exist
(b) f -1 = IN × N
(c) f -1 = f
(d) f -1 ((m, n))= (m, n)
Answer:

Option (c)

85.
For f : A → B, ∃ a function g : B → A  such that gof = IA, then _____.
(a) f is onto
(b) f is not onto
(c) f is one - one
(d) f is not one - one
Answer:

Option (c)

86.
If a ∗ b = ab on N, then 2 ∗ 3 = _____.
(a) 5
(b) 6
(c) 8
(d) 9
Answer:

Option (c)

87.
If a ∗ b = a - b, on Q, then ∗ _____.
(a) satisfies commutative and associative property.
(b) satisfies commutative property but not associative property.
(c) does not satisfies commutative property but associative property.
(d) satisfies neither commutative property nor associative property.
Answer:

Option (d)

88.
If a  b = a2b, on Q then -12  13 = _____.
(a) -118
(b) -112
(c) 112
(d) 118
Answer:

Option (c)

89.
If a  b = a + b2  on Q, then  _____.
(a) satisfies commutative and associative property.
(b) satisfies commutative property but not associative property.
(c) does not satisfies commutative property but associative property.
(d) satisfies neither commutative property nor associative property.
Answer:

Option (b)

90.
If a  b = a + b - 2 on Z, then  _____.
(a) satisfies commutative and associative property.
(b) satisfies commutative property but not associative property.
(c) does not satisfies commutative property but associative property.
(d) satisfies neither commutative property nor associative property.
Answer:

Option (a)

Showing 81 to 90 out of 145 Questions