Step-by-step explanation:
I missed the x >= 0.
therefore only positive x (and then renamed y) are possible for the reverse function
that is easy and quick.
y = x² + 2
y - 2 = x²
x = +sqrt(y - 2)
and after trading the variable names to a regular function definition we then have
y = +sqrt(x - 2)
so, D is the right answer.
