The function f(x) has a domain of "all real numbers, x > 2" as defined in the question. (There are no resulting square roots of negative numbers or divisions by zero involved here.)

To find the range:

• When x = 2, f(2) = 8
• When x increases from 2, f(x) becomes larger than 8 (Try substituting in some numbers to see why.)

Hence, the range is "all real numbers, f(x) > 8"

Here is the graph of the function, with an open circle at (2, 8) indicating that the domain does not include x = 2 and the range does not include f(2) = 8.

Domain: All x>2
Range:
All f(x) > 8

The function is part of a parabola. [See more on parabola.]

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