What does this mean exactly?
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Answer: Choice B [tex]y \le 0[/tex]
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Explanation:
They want to know what are all the possible y values here. The range is the set of all possible outputs of a function.
The largest y value is y = 0 which occurs at the vertex, in this case the highest point. There is no smallest y value as those arrows point downward forever.
So y is between negative infinity and 0, which means we write [tex]-\infty < y \le 0[/tex]
Converting that to interval notation leads to [tex](-\infty, 0][/tex]. Note the square bracket to include the endpoint.
The compound inequality [tex]-\infty < y \le 0[/tex] simplifies to [tex]y \le 0[/tex]
One way to describe this particular relation's range is to say "The set of negative real numbers with 0 included".
Side note: The domain is the set of all possible x inputs. In this case, the domain is the set of all real numbers.