Answers:
[tex](f \circ g)\;(x) = 4x^2 - 12x + 6\\\\(g \circ f)\;(x) = 2x^2-9\\\\[/tex]
The domain for both is "all real numbers".
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Explanation:
The work is shown below in the attached image.
The domain for each composite function is the set of all real numbers because we don't have to worry about things like dividing by zero, or taking the square root of a negative number. Any x value is allowed.
