The value of P(n, n - 1) is: - Vidyadip

MCQ

The value of $P(n, n - 1)$ is:

A
$n$
✓
$n!$
C
$2n$
D
$2n!$

✓

Answer

Correct option: B.

$n!$

We know that $\text{P}(\text{n}, \text{r}) = \ ^\text{n}\text{P}_\text{r} = \frac{\text{n}!}{(\text{n}-\text{r})!}$
Hence, $\text{P}(\text{n}, \text{r}) = \ ^\text{n}\text{P}_\text{n-1} = \frac{\text{n}!}{\big[\text{n}-\text{r}\big]!}$
$\text{P}(\text{n, n-1}) = \frac{\text{n!}}{(\text{n}-\text{n}+1)!} = \frac{\text{n}!}{1!} = \text{n}!$
Therefore, the value of $\text{P}(\text{n}, \text{n}-1)$ is $\text{n}!.$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q (1 Marks)" from Permutation and Combinations→Permutation and Combinations — all question types→Maths STD 11 Science question papers→CBSE Board STD 11 Science question papers→CBSE Board question paper generator→

Similar questions

If $R$ is a relation on a finite set having $n$ elements, then the number of relations on $A$ is:

The equations of the sides of a triangle are $x + y - 5 = 0;\;$ $x - y + 1 = 0$ and $y - 1 = 0,$ then the coordinates of the circumcentre are

The equation of the line passing through $(4, -6)$ and makes an angle ${45^o}$ with positive $x$-axis, is

If $z = 1 - \cos \alpha + i\sin \alpha $, then $amp \ z$=

The value of $\sum\limits^\text{n}_{\text{r}=0}\text{a}_{2\text{r}-1}$ is:

If the roots of ${x^2} + x + a = 0$exceed $a$, then

Let the lines $y+2 x=\sqrt{11}+7 \sqrt{7}$ and $2 y + x =2 \sqrt{11}+6 \sqrt{7}$ be normal to a circle $C:(x-h)^{2}+(y-k)^{2}=r^{2}$. If the line $\sqrt{11} y -3 x =\frac{5 \sqrt{77}}{3}+11$ is tangent to the circle $C$, then the value of $(5 h-8 k)^{2}+5 r^{2}$ is equal to.......

The sum of the series $\frac{1}{1-3 \cdot 1^2+1^4}+$ $\frac{2}{1-3 \cdot 2^2+2^4}+\frac{3}{1-3 \cdot 3^2+3^4}+\ldots$. up to $10$ terms is

If $\text{cosec x}+\cot \text{x}=\frac{1}{2},0<\text{x}<\frac{\pi}{2},$ then $\cos\text{x}$ is equal to

If angle between asymptotes of hyperbola $\frac{{{x^2}}}{{{a^2}}} - \frac{{{y^2}}}{3} = 4$ is $\frac {\pi }{3}$ , then its conjugate hyperbola is