what is the domain of f(x) = (1/3)^x ?
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Answer:
B
Step-by-step explanation:
There isn't any number that x can't be. Start with a graph to show how this could be so.
It is easy to see that x > 0 gives a line that goes very near the x axis. It is not quite so easy to see that it never touches the x axis. But if you recreate the graph in Desmos, you will see that is true if you spread the x's out.
It is not quite so easy to see that when x<0 the graph tips upward very quickly but again if you move the values of the axis around you will see there is no value that x cannot be.