Question

(X+2)! ÷ X! = 6 Com X > 0

Answer 1

(x+2)!
--------- = 6
x!

(x+2).(x+1).x!
------------------ = 6
x!

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

x² +3x +2 - 6 = 0

x² +3x -4 = 0

∆= 9 +16= 25 ==> √∆=5

x' = -b+√∆/2a = -3+5/2 = 2/2 = 1 ✓