Let be the real line. Consider the following subsets of the plane :
Which one of the following is true?
is an equivalence relation on but is not
Neither nor is an equivalence relation on
Both and are equivalence relations on
is an equivalence relation on but is not
As we learnt in
REFLEXIVE RELATION -
A relation R in A is said to be reflexive, if a R a ,∀ a ∈ A
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SYMMETRIC RELATION -
A relation R in A is said to be symmetric, if a R b ⇒ b R a,∀ a,b ∈ A
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TRANSITIVE RELATION -
A relation R in A is said to be transitive, if a R b and b R c ⇒ a R c ∀ a,b,c ∈ A
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S = {y = x + 1 0 < x < 2}
T = {x - y is an integer}
For T : (a, a) it is integer reflexive
(a, b) (b, a) it is integer symmetric.
(a, b) (b, c) (a, c) it is integer transitive.
So it is equivalence
For S : x = 1, y = 2 not equivalence.
Correct option is 1.
Option 1)
is an equivalence relation on but is not
This is the correct option.
Option 2)
Neither nor is an equivalence relation on
This is an incorrect option.
Option 3)
Both and are equivalence relations on
This is an incorrect option.
Option 4)
is an equivalence relation on but is not
This is an incorrect option.
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