It is known that the function f (x) is equal to one part of X, X

It is known that the function f (x) is equal to one part of X, X

Let x + 1 < 0, i.e. x < - 1, f (x + 1) = 1 / (x + 1); let x + 1 > 0, i.e. x > - 1, f (x + 1) = (x + 1)