Question

Resolva as equações x! / x-2 != 2 b) (2n+1)! / 2n-1!= 6

Answer 1

x!/(x -2)! = 2
.
x•(x-1)•(x-2)! / (x-2)! = 2
.
x•(x-1) = 2
.
x² - x - 2 = 0
.
(x - 2)•(x + 1) = 0
.
x - 2 = 0
.
x' = 2
.
x + 1 = 0
.
x" = -1
.
.
S = {( 2)}
.
.
.
b) (2n + 1)! / (2n - 1)! = 6
.
(2n +1)•2n•(2n - 1)! / (2n - 1)! = 6
.
(2n + 1)•2n = 6
.
4n² + 2n - 6 = 0
.
2n² + n - 3 = 0
.
(2n + 3)•(n - 1) = 0
.
2n + 3 = 0
.
2n = -3
.
n' = -3/2
.
.
n - 1 = 0
.
n" = 1
.
S = {(1)}
.
ESPERO TER AJUDADO!