Let R be a relation over the set N x N and it is defined by Then, R is
We have, (a, b) R (a, b)for all is reflexive
R is symmetric for we have
Hence, R is symmetric.
Then, by definition of R, we have
a+ d = b + c and c+ f= d + e
hence by addition, we get
a+d+ c+ f =b+ c + d+e
or a+f =b +e
Hence, (a b) R (e, f )
Thus, (a, b) R (c, d) and (c, d)R (e, f)
(a, b)R (e f)
Hence, R is transitive.
Clearly R is equivalence