The actual inverse function is:

And the domain is [0, ∞).
<h3>
Where is the mistake?</h3>
Remember that for a given function f(x) with a domain D and a range R.
For the inverse function, f⁻¹(x) the domain is R and the range is D.
Here, for the given function the domain is x ≥ 3 and the range is [0, ∞).
Then for the inverse function, which is:

(to check this, you must have that):

The domain will be [0, ∞) and the range x ≥ 3
If you want to learn more about inverse functions:
brainly.com/question/14391067
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