Inverse of the function of y = x2 + 4x + 4

Y = x² + 4x + 4 which nothing but (x+2) ².

Then y = (x+2) ²

To find the inverse f⁻¹ (x), follow the steps:

Just replace y with x and x with y

x = (y + 2) ²

OR

√x = √ (y + 2) ² → √x = y+2 and y = √x - 2

So f⁻¹ (x) = - 2+√x