Răspuns:
Explicație pas cu pas:
A = {1, 4, 7}
B = {1, 3, 5, 7, 9}
A x B = {(1, 1), (1, 3), (1, 5), (1, 7), (1, 9), (4, 1), (4, 3), (4, 5), (4, 7), (4, 9), (7, 1), (7, 3), (7, 5), (7, 7), (7, 9)}
B x A = {(1, 1), (1, 4), (1, 7), (3, 1), (3, 4), (3, 7), (5, 1), (5, 4), (5, 7), (7, 1), (7, 4), (7, 7), (9, 1), (9, 4), (9, 7)}