Question

Resolva as seguintes equações: a) 8 (x+3)!/(x+4)!=2
B) n!/(n-2)!=42

Answer 1

Boa tarde 

a)

8*(x + 3)!/(x + 4)! = 2 

(x + 3)!/(x + 4)! = 2/8 = 1/4 

inverse

(x + 4)!/(x + 3)! = 4

x + 4 = 4
x = 0 

b) 

n!/(n - 2)! = 42

n*(n - 1) = 42
n² - n - 42 = 0
(n - 7)*(n + 6) = 0
n = 7