Question

Calcule n sabendo que (n+1)!/n!=4

Answer 1

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$\frac{(n+1)!}{n!} =4 \\ \\ \frac{(n+1).n}{n} =4 \\ \\ n+1=4 \\ n=4-1 \\ n=3$

Answer 2

$\dfrac{(n + 1)!}{n!} = 4 \\ \\ \\ \dfrac{\not n!\ (n + 1)}{\not n!} = 4 \\ \\ n + 1 = 4 \\ \\ n = 4 - 1 \\ \\ n = 3$