Question

How do i graph the exponential function `f(x)=(1/5)^x` on a TI-83?

Answer 1

`Y1=(1/5)^X`

Explanation:

For `X` you use the `X,Theta`, etc button.

Problem could be your Windows setting. To start with I would set the x-windows from x-min=-5 to x-max=+5 and the y-window from y-min=-1 to y-max=+1.
This will give you a reasonable view of the graph. You can always expand or contract from there.