In: Advanced Math
Set A = {1, 2, 3, 4}, write a binary relation R on A that is reflexive, symmetric and transitive, with (1, 2),(3, 2) ∈ R.
Here A = { 1,2,3,4 }.
Now we define a binary relation R on A , then R must a subset of A × A.
R = { (1 ,1 ), (2, 2), (3, 3) , (4, 4), (1, 2), (2, 1), (2, 3), (3,2) }.
As R is subset of A × A , therefore it is a binary relation on A
with , (1, 2), (3, 2)
R.
Clearly ,R is reflexive as for all x
A, (x, x)
R.
R is also symmetric relation as if (x, y)
R
(y, x)
R for x ,y are member of A.
For any (x, y)
R and (y, z)
R
(x, z)
R , for x, y, z are member of A.
Another relation on A can be defined as -
R = { ( 1,1), (2, 2), (3, 3), (4, 4), ( 1, 2) , (2, 1), (2, 3), ( 3, 2), ( 2, 4), (4, 2)}.
This relation R is also reflexive, symmetric and transitive ,
with ( 1, 2), (3, 2)
R.