Answer:
hfyfjcigdgicgxissrixlgxrisitfhlxhosgifohdgidyoft8dhoxgidtixitxtidr7dististisigsurarisotxyiisraurxgkyd
Next time, don't procrastinate much.
Replace f(x) with y:
y = x^2 -1
swap the variables:
x = y^2 -1
Solve for y:
Add 1 to each side:
y^2 = x+1
Take the square root of both sides:
y = √(x+1)
To complete the solution use both the positive and negative values.
f^-1(x) = +/+√(x+1)
The last answer is the right one.
