Дана функция y = f(x), где f(x) = x - 1.

F(x ) = x - 1                           f(x+5) = x + 5 - 1 = x + 4

(x - 1) * (x + 4 ) 0
(x - 1)(x + 1)(x + 4) 0
    -            +                 -                  +
_______________________________
        - 4             - 1                   1
x [- 4 ; - 1][1 ; + )