Answer:
you need to know what domain and range mean... so remember domain is the input.... range is the output.. :)
Explanation:
the input .. "x" in this case.. can be any number .. so the domain is all real numbers.
the output.. or range.. is limited.. b/c the square on the 'x" will always make that number positive.. and then it's multiplied by the negative 2.... so that term will always be negative. : | hmmmm so when is that squred term the smallest it can be? hmmm when it's zero... soooo this function will .. at it's greatest point be 3 and go down from there...
the range is from -∞ to 3
see? :)