By applying AxesStyle -> Arrowheads[{0.0, 0.05}
we can make the appearance of the axis with an arrow at the extremities as follow :
Plot[1/x^5, {x, -20, 20}, AxesStyle -> Arrowheads[{0.0, 0.05}],
ImagePadding -> None]
Now, I want to make the axis thick at the same time.
The solutions I found use an AxesStyle rule, but I don't know how to cumulate two rules simultaneously.