Inverse Functions Help Required! (1 Viewer)

[ConHeo97]

Find functions which are the inverse of each of the following. State the domain and range of the inverse in each case.
22. f(x)=x^2 + 2x, x≥0

 

[braintic]

y = (x+1)^2 - 1 (x≥0) .... completing the square

Inverse:
x=(y+1)^2 - 1 (y≥0)

(y+1)^2=x+1

y+1 = +/- Sqrt(x+1)

y=-1 + Sqrt(x+1) .... choosing the + case to satisfy the range requirement

 

[ConHeo97]

OMG thanks so much you're the bomb! This question was going to drive me nuts. Very much appreciated.