Answer:
- domain: all real numbers
- see the attachment for a graph
- f(0) = 1
Step-by-step explanation:
The domain of any exponential function is "all real numbers."
The value of f(0) is ...
f(x) = 2^-x
f(0) = 2^(-0) = 1
_____
Comment on the graph
The free Desmos graphing calculator is an excellent tool for when you "need to see it graphed." It is available in a web browser or as an app for your Android or iOS platform. (I found there to be a little "learning curve", but once you determine the limitations, it is exceptionally useful.) On-line help and tutorials are available, along with some really good examples of use. I can't give you a link, but it is easily found with a search.
