Evaluate: n! (n - r)! when, n = 6, r = 2 - Vidyadip

Question

Evaluate: $\frac{{n!}}{{(n - r)!}}$ when, n = 6, r = 2

✓

Answer

Substi the value of n and r: $\frac{6 !}{(6-2) !}$
$\Rightarrow \frac{6 !}{4 !}=\frac{6 \times 5 \times 4 !}{4 !}=6 \times 5=30$

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