The carterian product `P xx P` has 16 elements among which two elements are (a, b) and (c, d). Find the set P and the remaining elements of `P xx P`.

Explanation

`(a, b) in in P xx P rArr a in P` and `b in P`
Also, `(c, d) in P xx P rArr c in P` and `d in P`
Thus `{a,b,c,d} in P`
Also, `n(P xx P) = n(P)n(P) = 16`
`rArr n(P) = 4`
Hence P = {a, b, c, d}
Hence remaining elements of `P xx P` are
(a, a), (a, c), (a, d), (b, a), (b, b), (b, c), (b, d), (c, a), (c, b), (c, c), (d, a), (d, b), (d, c), (d, d)