Question

Resolva essa fatorial 3!/4!+4!/5!

Answer 1

$\frac{3!}{4!} + \frac{4!}{5!} = \\ \\ = \frac{3!}{4.3!} + \frac{4!}{5.4!} = \\ \\ = \frac{1}{4} + \frac{1}{5} = \frac{5+4}{20} = \frac{9}{20}$

Answer 2

<=> 6/24 + 24/120 = 1/4 + 1/5
<=> 5 + 4/20 = 9/20.