The number of permutations of $n$ different objects taken $r$ at a time (without repetition) is denoted by:
A$n^r$
B$\dfrac{n!}{r!}$
C${}^{n}P_{r}$
D$\binom{n}{r}$
Answer & Solution
Correct answer: C. ${}^{n}P_{r}$
${}^{n}P_{r} = \dfrac{n!}{(n-r)!} = n(n-1)\cdots(n-r+1)$.
Related questions
Penalty for wrong answers : THERE WILL BE PENALTY FOR WRONG ANSWERS MARKED BY A CANDIDATE Penalty for wrong answers : THERE WILL BE PENALTY FOR WRONG ANSWERS MARKED BY A CANDIDATE For [[1,2],[2,4]], the determinant equals:If A is invertible, |A^{−1}| equals:For a 3 × 3 non-singular A with |A| = 5, the value of |adj A| is:For a non-singular square matrix A of order n, |adj A| equals:For non-singular A, B of the same order, (AB)^{−1} equals:For a non-singular A, (A^{−1})^{−1} equals: