Question

resolva as equações fatoriais
Me ajuda pelo amor de Deus ​

Answer 1

n!
-------- = 20
(n-2)!

n(n-1)(n-2)!
------------------ = 20
(n-2)!

n(n-1) = 20
n² -n -20 = 0 ==> ∆=1+80=81 => √∆=9
n'= -b+√∆/2a= 1+9/2 =10/2 = 5 ✓
=======================

(n-6)! = 720
(n-6)! = (6)!
n-6 = 6
n = 6+6
n =12 ✓