Each of the following defines a relation on N:

x is greater than y, x, y N


Determine which of the above relations are reflexive, symmetric and transitive.

Let R = {(x,y): x is greater than y x,y N } be a relation defined on N.


Now,


We observe that, any element x N cannot be greater than itself.


(x,x) R x N


R is not reflexive.


Let (x,y) R x, y N


x is greater than y


But y cannot be greater than x if x is greater than y.


(y,x) R


For e.g., we observe that (5,2) R i.e 5 > 2 but 2 5 (2,5) R


R is not symmetric


Let (x,y) R and (y,z) R x, y,z N


x > y and y > z


x > z


(x,z) R


For e.g., we observe that


(5,4) R 5 > 4 and (4,3) R 4 > 3


And we know that 5 > 3 (5,3) R


R is transitive.


Thus, R is transitive but not reflexive not symmetric.


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