If ^n P_3 + ^n C_ n - 2 = 14n, then n = - Vidyadip

MCQ

If $^n{P_3}{ + ^n}{C_{n - 2}} = 14n$, then $n = $

✓
$5$
B
$6$
C
$8$
D
$10$

✓

Answer

Correct option: A.

$5$

a
(a) By inspection $n = 5$.

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