Consider the relation R in the set Z of integers which is given by R = {(a, b) : 2 divides a - b}. Choose the correct option for the relation R: |
Not reflexive Reflexive but not symmetric Reflexive, symmetric but not transitive Equivalence relation |
Equivalence relation |
The correct answer is Option (4) - Equivalence relation for every $a∈z$ $a-a=0$ (divisible by z) $⇒(a,a)∈R$ (Reflexive) $(a,b)∈R$ ⇒ $a - b$ divisible by z ⇒ $b - a$ divisible by z $⇒(b,a)∈R$ (Symmetric) $(a,b)∈R,(b,c)∈R$ $a - b$ divisible by z, $b - c$ divisible by z $a - b + b - c$ divisible by z $⇒(a,c)∈R$ (Transitive) ⇒ R is equivalence Relation |