Question

B $\times$ A = {(x, a), (x, b), (x, c), (y, a), (y, b), (y, c), (z, a), (z, b), (z, c)}. Find set A and set B.

• A. A = {x, y, z}, B = {a, b, c}
• B. A = {a, b, c}, B = {x, y, z}
• C. A = {a, x, y}, B = {b, c, z}
• D. A = {b, z, x}, B = {c, b, y}

Answer 1

The correct option is B

A = {a, b, c}, B = {x, y, z}

B $\times$ A = {(x, a), (x, b), (x, c), (y, a), (y, b), (y, c), (z, a), (z, b), (z, c)}
Set A = set of second elements of each ordered pair of the set B $\times$ A
Set B = set of first elements of each ordered pair of the set B $\times$ A
A = {a, b, c}
B = {x, y, z}