inverse of y=sqrt(x+1)
The function is strictly monotone on x ≥ -1: it has an inverse on its range y ≥ 0
Isolate the square root: x + 1 = y, with y ≥ 0. Under this condition, squaring gives x + 1 = y2
⇥Let's solve in ℝ: x + 1 = y2
⇥Solution obtained: x = y2 -1
Renaming the output as x, the inverse is x2 -1, with domain x ≥ 0
▶Inverse function:   (x2 -1 for x ≥ 0)