^n C_r , ^n C_ r - 1 = - Vidyadip

MCQ

$^n{C_r}\,{ \div ^n}{C_{r - 1}} = $

A
$\frac{{n - r}}{r}$
B
$\frac{{n + r - 1}}{r}$
✓
$\frac{{n - r + 1}}{r}$
D
$\frac{{n - r - 1}}{r}$

✓

Answer

Correct option: C.

$\frac{{n - r + 1}}{r}$

c
(c) On simplifying you will get $\frac{{n - r + 1}}{r}$.

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