Answer :
9
Explanation :
The expression above signifies the Permutation expression
Permutation expression is given as nPr
The Permutation expression is calculated as:
nPr = P(n, r) = n! / (n - r)!
It the above question, we were asked to evaluate the expression 9P1
From the above question, we can see that:
n = 9 and r = 1
Therefore, the expression
9P1 = 9! / ( 9 - 1) !
9P1 = 9! / 8!
= 9 × 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1 / 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1
= 362880 /40320
= 9
Therefore, the evaluation of the expression 9P1 = 9