Let be the set of all integers and be the relation on defined as . Prove that is an equivalence relation.
Answer: is an equivalence relation.
Solution
Reflexive: is divisible by , so for all .
Symmetric: if then , so .
Transitive: if and , their sum is divisible by :
so .
All three properties hold.
Symmetric: if then , so .
Transitive: if and , their sum is divisible by :
so .
All three properties hold.
CBSE Class 12 Board · 2010 · Subjective