Answer : The sets P and Q are defined as follows:
P = {x : 4 ≤ x ≤ 5, x ∈ N} Q = {x : 7 < x < 10, x ∈ N}
For set P, the natural numbers (N) that satisfy the condition are {4, 5}. For set Q, the natural numbers that satisfy the condition are {8, 9}.
The Cartesian product of two sets A and B, denoted A×B, is the set of all ordered pairs (a, b) where a belongs to A and b belongs to B.
Therefore,
P×Q = {(4,8), (4,9), (5,8), (5,9)} Q×P = {(8,4), (8,5), (9,4), (9,5)}
As you can see, P×Q is not equal to Q×P. This shows that the Cartesian product is not commutative.