Permutation and CombinationHard
Question
If P(n, n) denotes the number of permutations of n different things taken all at a time then P (n, n) is also identical to : -
Options
A.n.P(n - 1, n - 1)
B.P(n, n - 1)
C.r! . P(n, n - r)
D.(n - r) . P(n, r)
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