Question
If a relation R on the set of integers Z is defined
as a R b β a - b β Q, then the relation is:Solution
We are given:
- The set Z (set of all integers)
- A relation R is defined by:
a R b if and only if (a - b) is a rational number
So b R a is also true. β The relation is symmetric. Transitive:
Suppose a R b and b R c are true.
Then a - b and b - c are both rational.
Add them: (a - b) + (b - c) = a - c, which is also rational.
So a R c is true.
β The relation is transitive. The relation R is reflexive, symmetric, and transitive. Hence, it is an equivalence relation . Final Answer: (A) Reflexive, symmetric, transitive
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