For example, there are 1, 2, and 3 elements in the R relation, corresponding to elements 2, 4, and 2 respectively.
Write the relation pair (1, 2) (2,2) (3,4).
Similarly, there are 1, 2, 3 and 4 elements in the S relation, corresponding to elements 3, 5 and 1, 2 respectively.
Write the relation pair (1, 3) (2,5) (3,1) (4,2).
When R*S is found.
It is determined by the relation (1, 2) in R and the relation (2, 5) in S respectively.
1→2→5 (1, 5)
Similarly,
2→2→5 to get (2,5)
3→4→2 to get (3,2)
Find S*R, (R*S)*R, should be able to?