Question

resolva as questões (n +2)! = 6.n! ​

Answer 1

(n +2)! = 6.n!

(n+2).(n+1).n! = 6.n!

(n+2).(n+1) = 6

n²+3n+2 = 6

n²+3n-4=0

∆=9+16=25 => √∆=5

n' = -b+√∆/2a = -3+5/2 = 2/2 = 1 ✓

n" = -b-√∆/2a = -3-5/2 =-8/2 = -4 (não presta)