Example 4.5.2  Inverse Relations

PRACTICE EXERCISES

1.   Let A = {a, c, e, f} and B = {b, i, m, u}. Let R be a binary relation from A to B as follows:

given any (x, y)  A x B,         (x, y)  R  x and y are both vowels

List the ordered pairs in A x B which are in R, and the ordered pairs in B x A which are in R-1.

2. Let A = {1, 5, 8} and B = {0, 3, 4, 7}. Let R be binary relation from A to B as follows:

given any (x, y)  A x B,        (x, y)  R  2 | x-y

Which pairs in B x A are in R-1?
3. Draw the arrow diagrams for R and R-1 in question 2.