What is the domain of the function represented by the graph?
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Answer: Choice C. [tex]x \ge -3[/tex]
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Explanation:
The domain is the set of all allowed x inputs.
Here we see that x = -3 is the smallest x value possible as it is from the left-most point. The graph goes on forever to the right, so there is no largest x value. Effectively infinity is the largest x value even though infinity is not a number.
We can say the domain is [tex]-3 \le x < \infty[/tex] which can be simplified to [tex]-3 \le x[/tex] or [tex]x \ge -3[/tex]
In short: x can be -3 or larger.