Relations and Functions  MCQs

MCQs of Relations and Functions

Showing 61 to 70 out of 145 Questions
61.
If f : R   R, f(x) =x, g : R   R, g(x) = x2 then. _____
(a) fof = x2
(b) gog = x2
(c) fog = gof
(d) fog ≠ gof
Answer:

Option (c)

62.
f:[-1,1][-1,1], f(x)=xx is _____
(a) one-one and onto
(b) many-one and onto
(c) many-one and not onto
(d) one-one and not onto
Answer:

Option (a)

63.
If f : R+ R+, f(x) =x3, g : R+ R+, g(x) = x13, then _____.
(a) fog = IR+
(b) fof = IR+
(c) gog = IR+
(d) gof = IR
Answer:

Option (a)

64.
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 reflexibe and transtive but not symmetric
(c) S is symmetric and transtive but not reflexive
(d) S is an equivalence relation
Answer:

Option (b)

65.
If f : R+ R, f(x) =(3-x3)13, then fof _____.
(a) is undefined
(b) = IR+
(c) = IR
(d) = f
Answer:

Option (a)

66.
If f:RR, f(x)=[x], g:RR, g(x)=sin x, h:R, h(x)=2x, then ho(gof)= _____
(a) sin [x]
(b) [sin 2x]
(c) 2(sin [x])
(d) sin 2[x]
Answer:

Option (c)

67.
If f : R - {-1}  R - {-1}, f(x) = 1 - x1 + x, then fof = _____.
(a) IR
(b) IR-
(c) IR- {-1}
(d) IR+
Answer:

Option (c)

68.
If f : R  R, f(x) = 1,x > 00,x = 0-1,x < 0and g : R Z, g(x) = [x], then _____.
(a) fog = f
(b) gof = f
(c) fog = g
(d) gof = g
Answer:

Option (b)

69.
If f:R(-1,1), f(x)=-xx1+x2 then f-1(x)= _____
(a) 1x2+1
(b) -signxx1-x
(c) -x1-x
(d) x2x2+1
Answer:

Option (b)

70.
If f : Z  Z, f(n) = 5n and g : Z Z, g(n)= n5,if 5 | n0,otherwise,  then _____.
(a) gof = IZ, fog = IZ
(b) gof = IZ, 5Ιn, (gof) (n)= 0 otherwise
(c) fog = IZ, 5Ιn, (fog) (n)= 0 otherwise
(d) fog = gof = IZ, 5Ιn, (fog) (n)= (gof) (n) = 0 otherwise
Answer:

Option (c)

Showing 61 to 70 out of 145 Questions